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Mazda MPV: Error Codes/TSBs/Recalls

curriercurrier Member Posts: 2
We have a 2000 Mazda MPV with the check engine light continuously on. It first showed error codes 304 and 306. Our regular general mechanic first replaced the manifold, and then the coils, with no luck.

We then brought it to a dealership, and they told us that they believe that a valve is not sitting correctly on the 4th cylindar. (We now have only error code 304). Specifically, they say that the cylindar has low compression, and the exhaust valve is slightly burned out to cause a misfire. They need to remove a cylindar head and do a valve job. The cost will be approximately $3200. We have already paid $700 with no luck in fixing this error code. Any ideas?


  • notasoccermomnotasoccermom Member Posts: 55
    It's been over a year since I checked in, had the 2nd/3rd hard shift problem back in Oct '04, they fixed that but I now have had a 1st/2nd hard shift problem ever since. Dealer told me it was normal, bull****. I lived with it for a while and then I finally yelled enough about it and told our service manager that I have to drive this van for at least three more years until it's paid off per my husband so I can get my horse barn built! So, I want it FIXED!!! Anyone else have the 1st/2nd gear shift shock? It happens in bumper to bumper traffic a LOT when you accelerate from a stop, but before it shifts into 2nd you have to let up on the gas, then depress the gas again and then it hesitates and slams into 2nd. It drives me nuts! I guess since I'm in rush hour a lot I feel it a lot. Anywho, he said they may just replace our whole transmission this time. We'll see.

    The choking/shuddering started at 37k miles, these cars have a built in timer to have problems right after the standard warranty is up I swear! Luckily we got a free 100k bumper-to-bumper warranty because of our original shift-shock problem, so it's covered. It's in the shop today, but our service advisor told me he already knew what it was, the ignition coil. I saw others posting about it so I though I'd chime in.

    I'll post when I get my van back and let everyone know the ultimate resolution to both problems!
  • dtownfbdtownfb Member Posts: 2,918
    Now that you know what the problem is, i would go back to the other mechanic and aks his advice and get a quote from him. You can buy and install a re-built engine for $3200. Otherwise, how does the MPV drive?
  • curriercurrier Member Posts: 2
    The van actually drives great. The dealership tells us that it eventually will start to have problems, and we risk damaging it even more if we do not address the check engine light. My concern is that the major repair which the dealership is proposing may not even be the problem. It would be a nightmare to pay the $3,200 and find that the check engine light probem does not go away. We did go back to the first mechanic, but he just lost his main worker, and is a bit distracted to handle this right now.
  • dtownfbdtownfb Member Posts: 2,918
    Do a Google search using "Mazda P0304" and see what comes up. I did this yesterday for my Intrigue that has a P0101 code. There were a bunch of websites that discussed this particular code and the steps to take. I bet you will find something similar for your situation. Not unless you want to spend $3200.

    Good luck.
  • kinkokinko Member Posts: 48
    I have a 04 (with 21k miles) and the gear change had always been very choppy/jerky. I had noticed the shifting became rough (sometimes the shock)going from 1st to 2nd, shortly after the TCM flash had been done on March 04. I had not noticed any 2nd to 3rd shift shock in the past year.
    I got the the 1st/2nd gear shift shock on and off in the past 20 months. Mine sounds exactly like what you described. Sometimes, I thouhgt that I might have confused the transmission control. During a stop/slow and go situation when I accelerate, sometimes I get the shock if I have to let my foot off the gas(due to the traffic) before it shifts to the 2nd(around 3000 rpm). I seems like the transmission is programmed to expect me to depress the gas hard during acceleration everytime.
    A few month ago, I unplugged the battery terminal for a reset and relearning of driving pattern. But now the jerky shifting is back during the slow and go. It shifts rougher if the O/D is off(o/d light on).
    Interestingly, I drove a used 05 last July at the dealer and that tranny shifted smoothly and nicely. So I guess it is not normal to all MPVs
  • lazyfoxlazyfox Member Posts: 90
    kinko go to your dealer and request TCM reflash if it wasn't performed yet, it should, but maby it wasn't

    US BULLETIN No: 05-003/04 DATE: 05/2004
    APPLIES TO: 2003-2004 MPV AFFECTED VINs: JM3 LW28** 30 367822 - JM3 LW28** 40 518096
    SUBJECT: Mazda Special Program (MSP03) - Shift Shock - Transmission Control Module (TCM) Reflash


    2003 - 2004 MPV vehicles built from April 1, 2003 through January 26, 2004
    2003 VIN Range: JM3LW28**30367822 - 378984
    2004 VIN Range: JM3LW28**40500013 - 518096


    The vehicle's automatic transaxle (ATX) may exhibit shift shock while the engine warms from cold to normal operating temperature. The symptom is intermittent, it does not occur all the time. The shift shock usually occurs during 1-2 or 2-3 upshifts, or 3-2 part throttle downshifts.

    In most cases, the cause of the shift shock is from the TRANSMISSION CONTROL MODULE (TCM) software calibration. A new software calibration is available on ESI to correct the shifting concerns.



    Inspect and repair all current dealer inventory according to the procedures contained in this service bulletin.


    When a retail vehicle is brought into the dealer for any type of repair or scheduled maintenance, inspect and repair the vehicle according to the procedures contained in this service bulletin.
  • subeedoosubeedoo Member Posts: 1
    We have the same car and similar problems, several error codes. Have replaced the exhaust manifold 2 yrs. ago, now in the last year have done a bunch of repairs for a nagging check engine light epedemic. To fix "lurching" during driving especially in the 40 - 45 mph range and some backfiring and sluggish starts from a stop - new Spark plugs, ignition coil, some other stuff and intake manifold, the latter got rid of the lurcing finally. But now the newest is a high pitched humming that gets higher the faster I drive. The tachometer is doing wierd things. I fear it is the transmission. We have spent about $1,000 in the last year to fix all ths stuff and at 105k miles I am not up for a new xmission. I am so disappointed with this car. Alternatives?
  • kinkokinko Member Posts: 48
    I doubt that I could duplicate the symptom in realtime. Because it is intermittent, it does not occur all the time. The dealer told me time after time that they won't do anything 'til they see it happens.
  • lazyfoxlazyfox Member Posts: 90

    When a retail vehicle is brought into the dealer for any type of repair or scheduled maintenance, inspect and repair the vehicle according to the procedures contained in this service bulletin."

    If your MPV was not reflashed with the latest software, they have to do it if your VIN is within the range of the TSB, read above. If they would not do it, contact Mazda and complain about the dealer or find another dealer who will do it.
  • lotazoomlotazoom Member Posts: 1
    We have an 04 LX with 28,000 miles. We had the shift shock issue back in 04. I described it as if someone was rear ending the car when it changed gears. The TCM flash fixed this issue. In Jan Feb 06 we had two more issues. When put in park the engine would rev to 2000 rpm and stay there. If you tried to put the car in drive it would stall and would not restart unless you waited an hour or so. Took to the dealership they found a faulty temperature sensor. It was telling the computer the engine was freezing. The second issue was a shutter while stopped and the engine was in drive. It also occurred at highway speed when coasting and then applying the gas. It felt like the transmission could not decide what gear to be in. Took it to the dealer ship, they tested, the mechanic took it home, found a bad ignition coil part code AJ51-18-100A Ignition Coil. Replaced and the car runs great again. No hesitation or transmission issues now.
  • sadboutwindstrsadboutwindstr Member Posts: 4
    105K and you're disappointed??!!! I've put 4 transmissions in two windstars since 1996! Together with the transmission each vehicle came with, that's 6 transmissions in 9 years. They go out at 40K miles, then the replacement at 20K after that! 105K without a new transmission sounds like a miracle vehicle!! Whatever your alternative, stay away from ford.
  • hokiefan33hokiefan33 Member Posts: 3
    Hi everyone!

    I have an '03 MPV, and I was wondering if anyone knows the location of the MAP sensor. I googled it and searched all over, but couldn't find anywhere that could give an accurate and definite location. If anyone knows and could post it, and possibly also post if and when they changed it, difficulty, cost, etc..., that would be great. I have 3 codes in the computer right now, but I suspect that all 3 are related to the MAP sensor.

  • criledocriledo Member Posts: 27
    I suspect you didn't find it because you are look for the wrong sensor. If I am right, you are looking for the MAF sensor, as in Mass Air Flow sensor. That on is located on the duct between the air filter and the intake manifold, right on top, you can't miss it. (Let em know if you don't find it and I'll send you a picture). The sensor is expensive; try cleaning it before replacing it. For that purpose use a spray that is an electrical cleaner and make sure it does not attack plastic. Good luck and let me know!
  • hokiefan33hokiefan33 Member Posts: 3
    Aren't these 2 sensors different? I know there is a MAP (Manifold Absolute Pressure) sensor, but is that the same thing as a MAF (Mass Air Flow) sensor? I know the '03 MPV has a MAP sensor on it, b/c I've already priced the part at AutoZone, and it is expensive, over $300 just for the part! Also, the code that came up when they checked it specifically referenced the MAP sensor, but didn't say anything about the MAF sensor? What do you think? If you can send a picture (of both sensor locations, if you have them, or just the one if that's all you have), that would be most helpful. I'm an accountant, not a mechanic, so things like this are tricky for me! :)
  • criledocriledo Member Posts: 27
    In that case I am the one that's mistaken, sorry, I thought you would have been looking for the MAF, not the MAP. I don't know the about the MAP, sorry! Why don't you go to the dealership, have them show you the part in the pats department and then ask them where it goes, they should point it out to you under the hood.....
  • dtownfbdtownfb Member Posts: 2,918
    I think it will be easier if you listed the codes.
  • hokiefan33hokiefan33 Member Posts: 3
    You're right, that might help, here they are:

    1) P0174 - "PCM determined fuel system for Bank 2 was too lean." Possible O2 sensor? I believe there are 4 of them, right and left before and after the converter.

    2) P0401 - "PCM determined there is insufficient flow in the exhaust gas recirculation system." EGR valve?

    3) P0106 - "PCM determined that input from the manifold absolute pressor sensor or the barometric pressure sensor has changed too much, without a corresponding change in engine operating conditions." Possible MAP sensor, and that this may actually be the cause of the other 2 codes, as well (i.e. fixing this one might fix all 3)? This has the highest cost for the part, at approx. $339.'

    Any help, and location description/picture of MAP sensor location, would be GREATLY appreciated!
  • rogerrabbitrogerrabbit Member Posts: 11
    The MAS (Mass Air Sensor) is immediately after the air clear - essentially a round tube with a wire sensor in the tube - must be more than that because it costs several hundred dollars (which is why trying to clean it before replacing makes some sense).

    Mine was replaced and drivability issues were solved - when the sensor is not working correctly, the bad readings send all sort of crazy fuel readings to the computer and cause the erratic performance. Not the only possible cause, but it was in my case (although I changed the spark plugs shortly thereafter).
  • husker92husker92 Member Posts: 44
    States EVAP emmission Control System Leak (small).

    On the web it says it could be the gas cap not on completely. It says to tighten it, reset the codes and see if it comes back (CEL). Can I reset the codes or does the dealer need to do that?

    Any help would be appreciated.

    Thanks - Jay
  • rickand2rickand2 Member Posts: 2
    I had check engine light coming on. At first I was told by 2 garages to twist the gas cap tighter after refueling.
    Turns out it was a valve a low compression in one cylinder. Very depressing after just 60,000 miles. I did maintain the car. It was not driven as a hot rod either. I would think twice before buying this year. I do not think Ford and Mazda
    used good sense before introducing this car.
  • bolingboling Member Posts: 1
    A friend's reader says it points to o2 bank one sensor one, where is this one located? do they have to be replaced in pairs?


  • mvlyangmvlyang Member Posts: 1
    What can you tell me about this code? I'm not sure if the "O" is an O or a Zero.
  • subearusubearu Member Posts: 3,613
    P0456, or p zero four five six = Evaporative emission control system leak detected (very small leak)

    Did you recently fill up the gas tank and forget to click the gas cap several times? Did you overfill the tank - ie, did you contine filling after the pump clicked off automatically? That can damage the charcoal canister system over time.

  • rafilevirafilevi Member Posts: 1
    I have 2001 Mazda Mpv with error code po304. I replaced the sparks and the coil, and checked the wires. I concern that I am going to pay more and more money with no results. I red your comments and it looks like it is not easy to fix. Do you solve your problem?What do you recommend to do? Maybe to get rid of the car??/
    Thank you- Rafi
  • 3pawdwolf3pawdwolf Member Posts: 2
    My 2003 MPV with 92k miles has a check engine light on and is reading codes:
    P0031 - Bank 1 Sensor 1 Heater Circuit Low
    P0037- Bank 1 Sensor 2 Heater Circuit Low
    It has been on for over a month and started blinking so I took it to a mechanic who tuned it up and cleaned the injectors and cleared the codes and said lets see what happens next. Well the check engine light came back pretty quick. I took it to Autozone and had the codes read. I'm thinking to save a little money if you folks can tell me which sensor to replace and where its located. Any help is appreciated.
  • aa0526aa0526 Member Posts: 29
    I have a 2002 Mazda MPV, 105K - new spark plugs, new wires and new air filter.
    But I have these 2 codes showing up (with the following options/hypothesis)

    PO174 and PO171:

    PO171 - Fuel system for bank 1 is too lean, Oxygen sensor recognized a rich or lean condition on one engine bank only
    1- Suspect fuel pressure or Mass Air Flow sensor
    2- Oxygen sensor defective
    3- Ignition misfire-repair
    4- Fuel injector problem

    PO174 - Fuel system for bank 2 is too lean, rich or lean air/fuel ratio condition engine bank two
    1- Suspect fuel pressure or Mass Air Flow sensor
    2- Failed HO2S21
    3- Ignition misfire condition
    4- Fuel injector problem

    Which ones should I ask the mechanic to look at?
    I don't want to go back and forth the car shop and just have the CEL keep coming back on...

  • nlsnls Member Posts: 65
    I think that intake air manifold gasket leak could also cause these codes, so that might be an area to check.
  • 3pawdwolf3pawdwolf Member Posts: 2
    I could not get anymore info so took it back to mechanic and he replaced the 2 sensors pointed to by P0031 and P0037. After clearing the codes it didn't take long for the check engine light to come back on. The mechanic told me it was back on and still reading P0037- Bank 1 Sensor 2 Heater Circuit Low. He suggested I take it to the Mazda dealership as he wasn't sure what to do except replace more O2 sensors. I don't really fault the the guy.
    So I'm out a total of $550 for the 2 visits to mechanic so far (I put this in for the benefit of those who search these error codes in the future)
    You folks have any wisdom to share?
  • rhandrhand Member Posts: 1
    This a frequent problem with 00 Nissan. It has been traced back to intake manifold gasket leak.

  • talntaln Member Posts: 2
    I would take nls's advice. I just had the same codes come up. My regular mechanic guessed it was either the O2 sensors or the gaskets when he saw the readings, but the dealer didn't even hesitate before warning me what it probably was. After doing their own check they confirmed is was the the intake manifold gaskets.
  • lone_rangerlone_ranger Member Posts: 2
    I know of a 2000 Mazda MPV with the same error codes. The owner took it to the dealer who told them it was the front O2 sensor. They are relatively easy to install with an adjustable wrench or the right size socket ratchet. (Lightening)
  • lone_rangerlone_ranger Member Posts: 2
    You can buy an OBDII reader for less than $150.00 and delete the code, then sell it before the code reappears. (Lightening)
  • whylandwhyland Member Posts: 2

    I have a 2003 MPV and also got a check engine light that showed P0037. I checked the code at Autozone, and then paid for the more expensive scan at my trusted garage, which returned the same code - "02 Sensor Bank 1 Sensor 2". Same as you, they want to replace one or two of the sensors for nearly $500. I'm hoping you can tell me how you resolved this issue before I throw too much money at it. Is it resolved? Thanks

  • kprime2kprime2 Member Posts: 5
    MPV 2001 LX. Check engine light P0031. I have an Actron CP9135 that is 3 years old. It cost $100. It does a beautiful job of reading and erasing codes.

    However, it is often difficult to diagnose ck eng lite problems from just the codes. The codes do tell you what parts might be involved, but not to what degree, or in what order, or whether a partial fault in another sensor is cascading to the code in question. With O sensors age causes a decline in performance. Thus you may get an intermittent code that does not always appear immediately.

    Note: The two sensors in front of the cats (catalytic converters) are the most important sensors used by the computer for determining fuel mixture. By tracking and responding to these two sensors the computer determines power, fuel mileage, rich/lean conditions which affect the life of the engine and the life of the cats.

    The second two O sensors tell the computer how well the cats are working. They determine whether or not you will pass an emissions inspection. Information from these sensors can tell you if your cats are bad. Of course the sensors have to be in good working condition.

    Just reading codes will always leave you guessing at what to replace. Even excellent mechanics can only guess at the problem with just a code.

    Four months ago I invested in a new code reader. I bought an Actron Elite Autoscanner Pro CP9190. You can buy them online for about $300. Now I know that seems like a lot of money but with the cost of repairs these days it will save you thousands. What is cool and better about this scanner? This scanner gives you realtime readings of the sensor outputs that are coming back to the vehicle's computer.

    I am diagnosing my MPV today because it's time for inspection again. Last year I barely passed by clearing the codes then driving the veh about 400 miles until the monitors all registered ready. I got away with that because the veh would run about 700 miles before throwing the OS2 code. This year will be different. Of course last year I did NOT have my new reader (CP9190).

    So what does the new scanner tell me that the original one can't? I can now watch a real time graph of the output from any sensor on the car. I can now see that my O2S22 (that's bank 2 second sensor) has a very erratic output. It only operates from about .3v to .7v. Further it's response time is highly degraded. The O2S21 is in great shape running from .1 to 1.1v with a fast response time. Both of my bank one sensors are working well enough not to trigger a code but the are running from .2v to about .8v and they respond slowly to changes in the fuel conditions of the engine. They are close to the end of their life span. That means my engine is running a bit rich, wasting gas, polluting the air, losing power, clogging my cats. If I replace them now (about $100 each) I can save replacing my cats for $2000. Otherwise running too rich will ruin the cats much quicker. Further, because they are near the lower end of acceptable they could also begin to throw intermittant codes as the weather temperurature changes. (other variables will also effect their performance). Why weather changes? Because temperature, air density, and moisture levels affect air/fuel mixtures and their related sensors.

    There is a huge advantage to having a scanner which will give you real time readings and graphs of the sensors. Even without any background you can spend a little time comparing sensors and figure out which sensors are under performing. Further you can do live experiments which help in diagnostic. For instance my O2S 22 is under performing badly. with the engine running and the scanner going I unplugged the sensor coupler. The engine continued to run just fine but the scanner voltages went to zero. I plugged it back in and wiggled the coupler to verify contact. With this little test I am more certain the sensor is bad and the wiring is ok.

    Another trick you could do with the same set up is pull a vaccum hose off and watch the sensor go low, showing that the fuel mixture is too low. This kind of simple experimentation could help you rule out air leaks. Rev the engine up and down, if the sensor shows good range .1 to .9 and quick response the sensor and the wiring are fine. If is show lean conditions during idle you likely have an air leak.

    In a nutshell. Simple code reading will totally leave you guessing, often lead you down the wrong path, and likely end up costing you far more money than it should have cost. For that matter, ANY mechanic that is making suggestions or diagnosis without a real time scanner cannot be giving you your money's worth. Find a friend or mechanic with a graphing scanner.
  • whylandwhyland Member Posts: 2
    Thanks Kprime. Good council on how these 02 sensors work and the risk involved in terms of not having to replace one of the cats.
  • kprime2kprime2 Member Posts: 5
    You are welcome.

    My 2001 MPV has 129K miles on it. I am also getting error code (P0428) This code basically means the cats are under performing. If I gave this code to a mechanic he would likely suggest the cats need replaced. They do not. It's a bogus code.

    This code is derived by the computers comparison of OS2 #1 relative to OS2 #2. However since I can see that OS2 #2 is operating well enough to turn the ck eng lite only occassionally, but definitely operating very poorly I know the P0428 code is a false code. The computer makes the comparison and determines the cats are bad. The computer does not do a reasoned analysis and give me a print out that say's "Hey dude, your second sensor in bank 2 is almost out of spec and therefore it looks like your cats are going bad. You need to replace that sensor so I can get a good reading". It just throws codes after a couple hundred miles.

    The sensor is not in complete failure, therefore I when I reset the codes the light does not come right back on. If you study how the computer works with the emissions portion of its job you will find out that after re-setting the codes all cars have to be driven through a number of test variables over several hundred miles before the computer will give it's opinion. That's why you read a lot of cases where a part is replaced and then a week or month later the light comes back on. It takes the computer that long to do a full running analysis of the engine performance.

    If you live in an area where they require emission testing you cannot just reset the codes and pass the test. After you reset the codes the code readers will report that your sensors are NOT ready. Not ready means the car hasn't been driven far enough for the computer to make it's analysis. After re-setting you then have to drive it for about 2 weeks, several hundred miles, before it will pass inspection. You can also find, on the internet, the exact driving conditions the computer is looking for and purposely go out and create those driving conditions. When you follow the plan your computer reports the sensors or conditions are ready. Once the computer is in the ready state, if there are no current or pending codes, you will pass inspection. You ck eng lite will not be on. However, if one of the sensors is performing poorly sooner or later the light is going to come back on.

    Today's engines are designed with fail safes. That is why there are so many cars driving around with ck eng lites on. When a sensor is bad the computer defaults to a known workable condition and the engine continues to run without any fine tuning by the computer. They do this so you won't get stuck on the side of the road with a dead engine. However, this condition produces poor gas mileage, less power, more pollution, and runs the engine too rich. That will lead to early failure of the cats.

    In my case for instance. I could have a mechanic replace O2S 22 and reset the light. Say I pay him $400. Then after 400-600 miles the light might come back on. Let say for instance if the computer feels that bank one in not performing within spec on just one bad weather day. I go back and the mechanic scratches his head and says well guess we will have to replace another sensor, or maybe he will guess my cats are bad and tell me I have to replace the cats and the sensors but he's not sure.

    On the other hand maybe my MAP sensor, which measures atmospheric pressure and effects the computers decisions is under performing. This could cause the computer to think my cats are not doing a good job because the engine is running to rich. See the computer doesn't "think" in a car. It only reports. It does not know why certain conditions exist; it only knows that some signal fell below parameters. It take human analysis to pinpoint the problem and determine if its a single item or the result of a mix of variables. The mechanic cannot make this judgment, any better than the computer, without running the car for a few minutes and watching a live performance of the sensors. He may even have to take it out and drive it, with a scanner in live mode, in order to see where and when the problem occurs.

    My new scanner can record all the signals over a period of time. When you get done driving you can unhook it and review the stored data. You can hook it up to your computer through USB and print out the data and the graphs. It can also be set to start recording only when a DTC code (diagnostic trouble code, you know the thing that turns on the ck eng lite) is triggered. For $300. it's an awesome diagnostic tool. It doesn't take long to learn how to read most of the outputs. Things like intake air temperature, engine rpm, speed, timing, stuff like that you can assess just by watching the scanner. I have 5 vehicles I take care of; all for family members. I can run comparison scans and learn kinda what to look for on the scanner. You don't have to go to school to figure this stuff out. All of today's engines run pretty much the same way. You can make valid comparisons from one car to the next and generally tell if the sensors are reporting good data.

    Excellent article on O2 sensors.
  • aa0526aa0526 Member Posts: 29
    The mechanic (not dealer mechanic) initially thought we should replace the following:

    1. Mass Air Flow Sensor
    2. O2 sensor (before or after cat converter)

    But after removing each one and cleaning them --- it turns out - the sensors were just dirty! I only spent for the labor + a little for diagnostics.

    Car runs like new again (at 110K)! :)
  • kprime2kprime2 Member Posts: 5
    P0031 My turn for emissions inspection came up again. My analyser indicated that the heater for O2S 11 (bank one sensor 1) was faulty. It would not pass inspection. I ordered all 4 O2 Sensors from a dealer back east, I believe this was the site. Paid $99 ea with low cost shipping.

    My MPV has 130K miles on it and the O2s are supposed to be changed at 100K so I figure just get them all done at once. Took it too a local mechanic (non-dealer) that has done some work for me in the past. He charge $120.00 to replace them all. CEL went out. I drove the van through the ready cycles and all lights were off. The emission managers were 'ready' so I drove it right over to the inspection station. It passed. :)

    Since your engine is over 100K don't be surprised if your O2 sensors start throwing codes again in the next year. I would order OEM parts and take them to your mechanic.

    Congrats on your current repair tho. :)
  • tcc21tcc21 Member Posts: 69
    I recently brought my 2003 MPV in since the Check Eng. light had come on for two days...then went off on it's own right before bringing it in. The dealer said that the code was to REPLACE THE CATALYTIC CONVERTER! $1000 job! I had never replaced one in 30 years of cars and I was quite upset. Have any of you heard of this issue with MPV's? I called another dealer to inquire and that person said not common, but it COULD happen. I have no other signs of problems...yet. Engine seems to be running fine and no 'loss of power' as is the telltale sign. Does this seem right? I have 99K miles on it and, of course, Mazda only covers this unit up to 80K miles! Is there any recourse?
    Also; had to have the fuel sending unit replaced due to gas gauge not reading correctly. THAT was under my extended warranty and would have been $200 cost.
  • aa0526aa0526 Member Posts: 29
    My 120K 2002 MPV ---- is experiencing very rough idling at neutral at 600.
    Putting the van in Drive smooths out the rough idling but the idling is still pretty lower than usual around 800.

    The EGR valve was replaced under the recall at 70K about 3 years ago.
    Should it get replaced again?

    There are no CELs or codes showing up ... what could be wrong?
  • nlsnls Member Posts: 65
    Idle Air Control (IAC) valve? Cleaning it might help, replacement is also very easy and part is not all that expensive.
  • nlsnls Member Posts: 65
    Idle Air Control (IAC) valve? Cleaning it might help, replacement is also very easy and part is not all that expensive.
  • jipsterjipster Louisville, KentuckyMember Posts: 6,064
    If not the IAC as nls suggested, I would think it would be the PCV hose ... located in upper back part of engine. Check for a hissing sound. Also, could be a faulty ignition coil.

    I would still check for codes at a Autozone, or somewhere done free. My MPV was running rough with no CEL. When taken to Autozone the code showed up on the scanner as a faulty ignition coil.
    2020 Honda Accord EX-L, 2011 Hyundai Veracruz, 2010 Mercury Milan Premiere, 2007 Kia Optima
  • aa0526aa0526 Member Posts: 29
    My MAZDA MPV 120K --- which has the rough idling at neutral ---- has the CEL now lit. Will bring it to the shop ...
    Will ask them to check the following:
    1. PCV hose
    2. IAC valve
    3. ignition coil

    Just curious ... how much would the labor for any of these be TYPICALLY?
    How long will replacing these take?

    Need to get a budget for this ... Thanks!
  • jipsterjipster Louisville, KentuckyMember Posts: 6,064
    A new PCV hose at the dealership is around $79. Some members at the MPV club have jury rigged other hoses to fit for less money. Some mechanics(the good ones) can put on a PVC hose without taking off the intake manifold. Most mechanics will take the intake off, which takes about an hour and half of labor. Most dealerships charge around $110 an hour for labor. You could take it to an independent shop for much less.

    Don't know about the IAC valve.

    Ignition coils are about $90 at dealership. You can buy them on-line for about $60. If the defective coil is on cyclinder #1, 2 or 3, then you're looking at big bucks, as the intake manifold must be taken off. So, you're again looking at an hour and a half to two hours of labor.If the defective coil is on cylinder 4,5 or 6 (the front cylinders closest to the radiator) then it is fairly simple... about 5 minutes. Pop off the engine cover and there they are.

    If it's a bad rear coil, have them check the PCV hose while they are in there.
    Good luck.

    Oh... to diagnose the problem, dealerships usually have a $70-$90 diagnostic fee.
    2020 Honda Accord EX-L, 2011 Hyundai Veracruz, 2010 Mercury Milan Premiere, 2007 Kia Optima
  • aa0526aa0526 Member Posts: 29
    Problem solved!

    The PCV hose needed to be replaced.
    The Mass Air Flow Sensor needed to be replaced too. This was the 3rd time this caused problems --- each time, I just had it cleaned.

    Initially - the mechanic was looking at replacing all the ignition coils --- we went back and forth --- he finally agreed to look at the PCV hose ---- I was right. It was a good thing the mechanic was very honest.

    So --- PCV hose + MAF Sensor --- plus, I got new spark plugs and oil change .... van runs great again.

    BTW --- the mechanic refuses to install my after market BOSCH +4 Ytrium plugs. He said Mazda swears against them. This is the 3rd time I've heard this... so I need to return these to Kragen now...

    What's wrong with BOSCH spark plugs? He said they are 'no good' for Mazda cars and vans.
  • jipsterjipster Louisville, KentuckyMember Posts: 6,064
    How much were you charged for the PCV hose and MAF sensor?

    I've heard Bosch was weak also. It's a Ford engine so, Motorcraft (OEM) or NKG plugs are the best.
    2020 Honda Accord EX-L, 2011 Hyundai Veracruz, 2010 Mercury Milan Premiere, 2007 Kia Optima
  • aa0526aa0526 Member Posts: 29
    This data is from SF Bay Area...

    1. Parts - $ 360
    - MAF sensor - $180
    - PCV hose - $82
    - Spark plugs - $36
    - Other parts (2) - $40

    2. Labor - $260 (includes oil change and install new spark plugs)

    The error codes were PO 300 and PO 171 (lean air mixture).
    There was one more but this was due to PO 300 and PO 171.
    I still don't understand why BOSCH plugs are crap ... I'll use them on my Lancer instead... maybe that will work.
  • classicsplayerclassicsplayer Member Posts: 3
    i needed to replace my vacumn hose assembly to correct the same problem
  • dannyyodannyyo Member Posts: 14
    I've had this 2003 MPV for almost 6 years now. Have about 72K miles on it and it's had a lot of issues. At 44K miles the "check engine light" came on"....Diag code p2404, internal failure of liquid purge box, It was replaced under warranty, the whole thing would have cost $677 if it wasn't for the warranty. At 45K miles I had to replace the water pump for $270. It also had the "recall" work done back in 2004 for 2204H PCV, SSP6 Fan control module. I have a '02 Honda Accord with 150,000 miles on it and the only major service was done at 100k and nothing else besides the regular maintenace (oil change, tire rotation, etc). In comparison MPV is terrible...well it is a "Ford"!!! I regret buying it and I should have paid extra for the Honda Oddsey or Toyota Sienna. Has other people experience lot of issues with their MPV? It's a great looking minivan, but it seems unreliable.
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