By accessing this website, you acknowledge that Edmunds and its third party business partners may use cookies, pixels, and similar technologies to collect information about you and your interactions with the website as described in our
Privacy Statement, and you agree that your use of the website is subject to our
Visitor Agreement.
Comments
do you work? (LOL)
Umm, only when I have to.
Meade
Hey, gotta keep doing it there, or no free tires ...
The wife and kid and I are taking off on a trip to Pennsylvania on Thursday. This will be my first long interstate highway trip (probably close to a thousand miles after all's said and done) in the Mazda3, so I'll be very interested in seeing what kind of gas mileage I can squeeze out of the car. We'll be loaded to the hilt with passengers and luggage, and the speed limit on at least one interstate in West Virginia is 75, so I don't think my mileage will be as high as it *could* be ... but this'll still be interesting.
Meade
Question is: will the light go off by itself eventually (and, if so, after how long?) or do I need to have a mechanic somewhere reset it?
Thanks.
-djg
Hey, that was my plan for this fall. Are you going to Wilmington or Harrisburg? Let us know the high points of your trip and have a safe drive and grand old time in colonial country!
If you have tightened the cap and the CEL stays on, it sounds like you may need to have the computer reset. I thought that involved removing the battery cable and then reinstalling it. I'd call the service desk at the dealership.
Meade
Steve
The good news is - if your AC is this bad then even Mazda may try and fix it.
A good AC should blow air in the low 40's - even if the temp outside is 95 degrees - Mazda has different standards (much lower - like 48 -52 degrees is considered acceptable)
Did it ever blow colder air?
According to the ambient temperature chart it shows a standard of about 40F to 52F. I am far from that....gee I would be happy with 52F
Daryl
I think its because the evaperator is so small (really undersized) when the compressor cycles on it quickly cools the evaperator down - once the temperature sensor (located in front of the evaperator) hits the set point it sends a signal to the compressor to shut down. As soon as this happens you get warm air - then it starts all over again as the compressor cycles back on.
With most (correctly designed AC systems) the amount of air flow moving through a properly sized evaperator keeps it from going below the set point (normally around 32 degrees) until the area being cooled actually gets cold.
The thing that really highlights the weakness in the Mazda3 system is the compressor shutting down - even though the car is still burning hot inside.
Very poor design -
The sad part is Mazda will not do anything to fix it - but the REALLY sad part is they just keep putting the same crummy system in the new models - no changes - next summer you will see posts from people who bought 2006 models asking about weak AC performance.
audi8q, any way of a Mazda tech checking by VIN to see if the diffuser plate is already installed?
Would you live with the air temp out of your vents at 64F to 66F ??/
If so tell us. But than maybe it's all in my head... :mad:
Mine will freeze my head (6' 3") if i have the vents tilted towards the driver. Low 100's.
The only gripe I have with the HVAC is the inability to direct more air flow to the doors...since the tinting is substandard.
The first thing I do is test the calibration - I PACK a small glass with crushed ice - then fill it with water the temp should be between 32 & 32.5 - Then I boil some water the temp at the surface should be between 211.5 and 212.
Although these tests prove the thermometer is accurate (+/- .5 degrees) at only 2 points unless you have a mercury thermometer it is about as good as you can do for a home test.
I have seem very expensive thermometers be off by 8-10 degrees - so don't feel like you need to spend alot to get an accurate reading.
The hard part is handling the fuse panel - that must be moved out of the way in order to get to the trap door covering the ac evaperator. I was able to move it over far enough so I could get to the door without disconnecting anything. It is a very tight area to work in. I would not try this unless you have some mechanical ability plus are able to lay on your side 1/2 way in / out of the car - not very comfortable position. The next day I had a sore neck!
Conclusion: the dark dash/interior is the culprit. I did a test this morning on my 30 minute drive to the dealership for an oil change. There was some fog so sunlight was not a factor. Temp coming out of the vent was 80 while outside temp was 78. This temp was the same at the beginning, middle and end of my commute. Yesterday, I did the same test on my drive home. The car had been sitting in the sun all day long; went out to lunch, though. I can’t recall the numbers except that the difference was north of 8 degrees at the end of my drive after having used the a/c for the entire drive. The difference at the beginning of my commute was so large that it isn’t worth mentioning; most likely not a fair assessment, either. In both tests, the HVAC mode was set to “fresh air” mode. I do believe the dash, in particular, not only absorbs heat at a quicker and greater pace than a lighter colored dash, but it also retains/stores and radiates this heat for a greater period of time than a lighter color. And retention is more than skin deep. Besides the ambient temp being off by 15 degrees, the only other difference between the 2 tests was the vehicle sitting in direct sunlight for an extended period of time vs. sitting overnight. If the heater core or the engine were a significant factor to the air coming from the vents, the results from the both tests would be much closer.
BTW – could the reason for the heater core being placed so close to the evap is so that the evap doesn’t reach the min set point too quickly or so the evap doesn’t freeze over?
How about this for generalization: defective units are unavoidable. Even though I side with those who think their a/c systems work fine, I truly believe some systems are/were defective. Examples of a defective system are: R134a leaking out; compressor cycles on forever or cycles on for 10 seconds and off for 10 minutes; vent temp never gets below 50 in 100 degree ambient after it is on for 10 minutes (actually, stabilizes above 50 in 100 degree ambient after 10 minutes of use); constant stench or odor. If I had anyone of these problems and they were to be fixed properly, unless the air coming out of the vents drops to below 40 with the a/c on, I would be less than satisfied. Since I don’t have a defective a/c system and even though my previous car measured as low as 34 degrees (stabilized at 37 with ambient temp of 90), I’m satisfied with the a/c system set up. Ambient temp mid to upper 90s; after 10 minutes of use in recirc mode, the lowest reading was 43 while the highest was 48; stabilized at 45 (add a couple degrees to all numbers for fresh air mode)
Does it really matter if its because the compressor is always shutting off - or if the evaperator is WAY to small - or the fan is weak - or the black color holds heat?
If Mazda puts a black dash in the car then they should also put in a AC system that is strong enough to over come the additional heat load. RIGHT?
I don't see how anyone can say (not that you are saying this BTW) - the AC works fine - its the black dash that is causing the car to feel hot.
You see the way I look at it - the BIG issue here is Mazda will not fix the car -If you get one that has a crummy AC then you are just plain stuck. Live with it - trade it in at a large loss are your only choices. Mazda really should be stepping up and fixing this problem.
As far as the heater core location - it is normal for the heater core to be close to the evaperator - when in defrost mode the air should flow through both.
The reason I wanted them to check it out was I was getting a temp reading of 64F to 68F from the vents. The car was sitting in a garage, so was not overheated by the sun, pulled it outside in the sun had the A/C on. Recir on etc. ( I read the manual). Sat for 5 minutes with fan speed at 2 and the best temp I could get was the 64F-68F readings. Had a thermometer resting against the vents. All 4 upper vents opened. The dealer checked the vent temp with the side 2 vents closed. Now with my luck the temp outside had dropped to about 75F from the previous day temp of 90F. The dealer got 51F to 52F, in spec. they used a prob thermometer about 6 inches long. Of course the car was indoors. I told them what I got and they said I didn't let the car run long enough to get the A/C up to operating temp. Also the interior is black which doesn't help to keep the car cool. My windows are tinited with 35%. Also told them that the compressor seemed to cycle often, like every 10 to 12 seconds. They said it was normal in hot weather. Also I asked about the diffuser plates and they said all 05's had the diffuser plates installed at the factory so they wouldn't check if it was actually installed.
If one of their excuses is the black interior, correct me if i am wrong but is this car the only car with a black interior? Don't think so. So how can other auto makers engineer a acceptable A/C, I have owned cars with much larger interiors and the A/C would freeze you out in temps over 90F. One was a light coloured and the other a dark interior.
I ask this exact question to the Mazda (corporate) technical expert that looked at my car.
His answer was - no - that would not work - the result would be a frozen evaperator.
The water on the evaperator would start to freeze - once that happens you get reduced air flow and even more ice build up. At some point the air flow would be 100% blocked and you would have no cool air. The internal temp of the evaperator is already close to 32 degrees - maybe even a little below freezing.
This is my own opinion / theory -
Mazda used the same size compressor in the Mazda3 as the Mazda6 2.3L - (I think someone posted that they checked this out and said they were the exact SAME compressor)
But the evaperator in the Mazda6 is much larger than the one in the Mazda3. So the compressor - because it is larger than it needs to be - over runs the dinky little evaperator that is in the Mazda3 and must shut down all the time (quick cycle).
The result is - cold - cool - warm - cold - cool - warm air and a car that never really cools off completely.
Just one more side issue - if you keep your car a long time - (past warranty) you should plan on a compressor failure. The quick cycle on and off is just about the worst thing you can do to a compressor.
They can tell exactly what the temperature of the evaperator is when the compressor shuts off by using a set of refrigeration gauges. I think it is the pressure reading on the high side - (but I am not 100% sure )
They have a chart for R-134A - I am making up the numbers - just as an example:
250 PSI = 45 degrees
255 PSI = 42
260 PSI =40
300 PSI= 31
They just monitor the PSI and wait for the compressor to shut off - then compare the gauge reading with the chart and they know if the sensor is working - shutting the compressor down at the right temp.
Mine check out fine -
1) the evaporator is too small to cool the required volume of air
2) there isn't enough air volume moving thorugh the evaporator
3) the air is getting heated after it gets through the evaporator
The problem is not the compressor -
I also ask the Mazda service manager if adding a second radiator fan would help - by getting more air flow over the condenser -at first he though yes - then he talked with the Mazda corporate tech - and he changed his mind and said it may help a little bit while at idle on very hot days (which is one of my problems) but said the fan shuts down at about 50 MPH - so adding a second fan would do nothing to improve AC performance at highway speed.
The thing about air volume over the evaperator is a little complex - more volume forced through this dinky evaperator would do no good - just stick a thermometer in your vent and see how much the temp drops from fan speed 1 to 4. If the Evap was larger THEN more air would solve the problem - because the larger surface area could handle the added flow.
The sad thing - he was right - his old Honda AC worked better than my new Mazda.
I understand - and wish I could give you some advise - the bottom line is - if you get a Mazda that has a weak AC you are SOL. Mazda does not see this as a problem - will not fix it - and does not care.
Turn it on on hot days, I have also been thinking about a second fan.
Having a manual switch would work just fine -
Other options are - tie it into the positive (hot) wire that controls the compressor - then every time you turn on the AC the extra fan comes on automatically. This was the method I planned on using -
You can also buy a kit that includes a sensor that you hook on / or into the radiator - then you set the temp you want the fan to come on at. This method would be a waste as far as AC improvement - it is more to solve engine over heating problems.
They did sell these fan kits at Walmart / AutoZone / Pep Boys - I was going to put one on 4x4 truck I used off road - but never got around to it - When I checked these stores a few months ago none of them still sell the kit.
The guy at AutoZone gave me his $.02 - said that I could buy an after market fan blade that would fit on the stock fan motor and pull more CFM of air than the stock blades. Which is a pretty good idea if you could find one - he though they were a common item for trucks - but did not know about a Mazda3.
One more side note - I never got around to it - but just for fun may give it a test.
I have an air compressor and was going to use it to blow extra air through the condenser - (while the car sat at idle!) and see if it had any impact on the temp of the air coming out of the vents. That way I would have some idea if the extra fan would actually do any good.
I do feel bad for you as our '05 S a/c works great down here in South Florida. Your's will never be satisfactory to you...never! Spare yourself any more anguish and move on. Get another economy car with a/c that meets your needs and be done with it. Your mental health will thank you in the long run!!!
The Sandman
I have looked for a replacement - but don't really see anything out there right now that I want - the new Lexus IS & 2006 Civic both sound good - but they will not be out until fall.
My wife really likes the looks of the Mazda6 - but now that I know what a poor company Mazda is - it would be hard to buy anything from them again. Which is really a shame - the Mazda3 could have been the first of many - since we seem to buy a new car about every other year - its too bad Mazda does not value repeat business.
The Sandman
The fall is only weeks away, Bill, and both cars look very interesting for different reasons. Being Toyota and Honda their first year reliability is probably better than average. We're rooting for you!
Mazda does not value repeat business
I guess that depends on whose business.
I may be reading between the lines (although it seems loud and clear to me) that you think I have been a "bad" customer. Let me set the record straight.
I have never been angry - made threats (like I will sue you!) to anyone at Mazda or the dealership. I have always treated them in a professional manner - and have always maintained the vehicle per the Mazda requirements. I paid the amounts that were negotiated - my check did not bounce. What else should a person do to be considered a good customer?
I ended up with a car that had many many many defects. This is not just an opinion - like I really like the way the dash looks or that Lava orange color makes me want to throw up - this is just a plain fact.
The DEFECTS in my car are not something that I just dreamed up - they are real - but don't take my word for it - go read the TSB listings FROM MAZDA! The only problem that is not now covered by a TSB is the harsh shifting auto tranny. Anyone want to bet that - what Mazda says is a NORMAL shift now will eventually be considered a problem and have a TSB issued?
So If I come across as an unhappy customer - that would be true - hard to think that anyone with all of these problems would say - best car I ever bought! But at the same time I really still like the Mazda3 - its loads of fun to drive.
I do understand how someone who was LUCKY enough to buy a Mazda3 with no problems could really like the car.
But luck should not be the deciding factor - Mazda should stand behind the cars that they sell - if they give someone a complete lemon then they should do something EXTRA to make it right - rather than just say - ITS normal.
I would look at it this way - the car (if not for all of the defects) could be considered very good - its MAZDA the company that is the problem.
All it would have taken to make me a happy customer is - admit that yes the AC system in your car is defective - and then FIX IT so it blows enough cold air so that it keeps the car cool. Admit that yes the brakes grind - and fix them - admit that the front end shouldn't make loud thumping noises on every little bump - and FIX IT - bla bla bla -
But instead Mazda always takes the position - ITS NORMAL - and then a few months later - here comes a TSB to FIX the DEFECT - I have had problems with other vehicles - major tranny problems with a 1990 Toyota and a loud clunk in the drive shaft of a 1998 Tahoe - both Toyota and GM service told me - they are aware of the problem and are working on a fix - then they put me on a list so I was notified when the problem was solved so I could come in and get the repair done.
We recently ordered a new living room set (couches, tables etc). A few of the pieces had defects and they were replaced/repaired promptly. This 5K purchase was no where near the cost of a new car, but I would expect the same treatment from an automobile manufacturer as a furniture manufacturer.
i.e. If you sold me something that is broken fix it or take it back