Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!





Nissan Altima Engine Failures

1111214161733

Comments

  • puds2002puds2002 Posts: 1
    I have an 2003 Altima and I like you have had various problems. Currently, the 2003 2.5L Altima is having problems with the power valve screws coming loose and going into the cyclinder. I understand that it is a recall on 04 models but Nissan does not want to do anything on the 03 model stating that it does not fall under the recall even though it is the same problem.
  • I HAD a 2002 Altima with lots of problems, Replaced the pre cat, Check engine light stayed on. I took it to the dealer and theyt told me I needed a new engine, I contacted Nissan Headquarters and they did say they were sorry, but nothing they can do, it wasnt a recall issue. I finally did the smart thing, Rather then stress myself out, I got rid of the Altima and bought a used Acura.. Thi s Acura is awesome!!! I would never buy a Nissan again, They dont stand behind there product.. Read Reviews and search the web before you buy~~~
  • Congratulations Smoothride!
  • ndiboyndiboy Posts: 36
    I am new to this site and live in Nigeria.I have learnt a lot about this 2002 2.5s Altima that I am afraid to drive it.I bought a used one with 73000miles on it.Its an American spec and so far, no problems except increased noise when i put on the a/c and the horrible suspensions.
    My question is since the emission is not checked where I live is it better to remove the CAT?
    Thanks Onuchukwu Chuma.ndiboy@yahoo.com
    2348033974181.
  • ndiboyndiboy Posts: 36
    Thanks for all the assistance.I have critically and painstakenly looked through the pics of the engine tear down, build up as well as the cat unplug, and they are beautiful but not too clear.
    I was expecting to see this cat stuff in one bit, but to no avail.One thing that is not clear to me is the whitish brown material in the container.Is it the stuff that is blocking the exhaust? Then there is another hole there, probably after the plug was removed, please I need more clarification now that I have seen the pics.
    The pre cat, I must confess i didnt see it.I tried looking into the manifold when it was lowered but i couldnt identify anything I could call the cat.I thought the cat will be something big that I will easily see.
    I need these things to be clear because I will like to remove the one in my Altima 2002 car,especially the pre cat,early before any problem starts.Mine is around 76,000miles now.
    ED,I need early and fast response,thanks and God bless you.I want mine to run like your daudhters car!!!!!! I love the car,stay in Nigeria, so if the car develops a problem,it gonna be terrible.
    Chuma.
  • Chuma,
    I'll be glad to help clear things up. Yes, you have a good Idea to remove the pre cat before the problems start, especially since you don't have emissions inspections.
    The best way to refer to the pictures is by NUMBERS, since there are about 700 pictures or more.
    The pre cat is built into the exhaust manifold. The top of the exhaust manifold, as it is being removed, is shown in teardown picture DSC06900. The bottom of the exhaust manifold is shown in teardown pictures DSC06930 through DSC06934, it shows views looking up inside the bottom of the exhaust manifold. Normally you would see the precat there, but in those pictures it is gone, the exhaust manifold is EMPTY. If the precat was there, you would see a screen in the bottom that holds the precat material above it. In this case the screen failed and the screen and all the precat material got blown out of the exhaust manifold and was blown down the exhaust pipe into the SECOND cat. When the material got blown down to the SECOND cat, it plugged up the second cat. That is when I had to remove and unplug the second cat. And yes, that brown and whitish material IS the contents of the SECOND cat plus the contents of pre cat. What happened now is that both cats are hollowed out, the pre cat and the second cat, giving a wide open exhaust, of course it still goes through the muffler, like a regular exhaust.
    Looking at the unplug cat photos, photos DSC06096 & DSC06097 show the old cat material that was removed from the second cat. This contains the material from the pre cat (first cat) and second cat. Then photos DSC06098 through DSC06100 show the hollowed out inside of the second cat after the contents have been removed.
    Photo DSC06087 shows the inside of the second cat BEFORE the contents were removed, the cat is plugged in this picture. What you see is the screen that holds the cat material in place, but the material had got wet and compacted, and the exhaust gas could not flow through it. The cat normally works by allowing the exhaust gas to pass through the cat material and then through the screen and then on to the muffler. The purpose of the screen is to hold the cat material in place. Once ithe cat pluggs up, it's no good anymore unless you unplug it or replace it. Unplugging the second was fairly easy once I had it off the car, just use a hammer and a metal punch or small diameter piece of pipe to hammer the stuff out.
    If you look into the bottom of the pre cat, you should see a screen just like in photo DSC 06087, unless the material has already blown out. You could clean out the pre cat the same way, break the screen and material out with a piece of small diameter pipe and a hammer. I think you should be able to hollow out the pre cat from under the car by removing the exhaust pipe and breaking out the material through the bottom opening, but be careful to not damage the oxygen sensors. It is best to remove the second oxygen sensor before you attempt to break the material out of the pre cat. You can run the engine for just a few seconds to blow the loose material out of the precat. After the pre cat is hollowed out, the service engine soon light will come on shortly thereafter, because the SECOND oxygen sensor will read the SAME as the FIRST oxygen sensor. To avoid this, you will need to add the O2 cheater at the SECOND oxygen sensor to make it read differently and for the light to stay off.
    Hope this helps,
    Good Luck,
    E.D. in Sunny Florida USA
  • ndiboyndiboy Posts: 36
    Good morning, well its morning in Nigeria, probably not where you are.I read your notes while watching the pics and its so much clear now.Pics DSC6932-34 contains a whitish ring like a loop opposite the O2 sensor ,I wander what that is.
    You mean the hollow in the cat unplug pics DSC06098-100 is all that the exhaust gas needs to move out?.
    Before I go further, I want to let you know someother things.I have been really afraid for this car because before and since I bought I have been reading a lot about it, Camry and Accords on the net, reviews etc The reviews have been that of mixed feelings for all the cars so I decided to go with this with this innate fear.The engine looks new and clean for a 73,000miles car so I was wandering is this not one of those the engine has been worked on and sent to Nigeria?.
    One sunday morning,about 2 months ago, I started the Car and after some seconds i heard a sound like something has dislodged inside the bonnet and i thought it was the cat since I have read several reviews of it coming off and damaging the engine.I was already looking foward to the engine dying but the noise stopped as if the stuff has dislodged and off we drove to church and till now nothing has happened.I change the oil every 3months with 4litres, and the filter every 6months and the oil level remains the same.
    Is there a way of knowing if the pre cat has been removed? Do they remove it before sending the cars to Nigeria?
    When I bought the car, the service engine light was on and I complained because of the reviews I read on the net about it.Later since it was not giving any problems and many cars down here show that, I ignored it.I changed the oil and filter, it still remained but after taking it out on a journey of about 500km I noticed the SES light has gone off.It remained off until about 3 mths later when it came on.I always turn the fuel cap several times after refuelling.I serviced it again ie changed the oil,the light remained.Now I travelled again about the same distance as the previous one and noticed that the SES light has gone off again(2weeks ago), and has remained off till now.My question now is can one use the light to gauge when to change the oil?
    I am presently on a cross country journey in the Niger Delta area and will be here in the next one month so I will try and remove the pre cat when I get home.
    Since you said the engine is good when you had a look at it,will you recommend it for somebody? since every car has its own fault.
    The noise I heard that sunday,can it be the pre cat dislodging?My only observation is that when the car is idling, if you rev it there is a little drag between the idle tachometer level(0.5) and 2.0, but its not felt when the automatic gear is engaged.You know this car so much that If I were in your position, I will erk out some living from it.
    Thanks for your concern and prompt response, its highly appreciated and looking foward to response to the questions raised above.
    Chuma.
  • PART ONE of TWO
    Q. "Pics DSC6932-34 contains a whitish ring like a loop opposite the O2 sensor ,I wander what that is."
    A. There are two whitish rings in picture DSC06932, they are the outer ring support for the screens. The lower screen ring is in place just above the oxygen sensor. The outer ring is all that is left, the screen is blown out, missing. You can also see the upper screen ring, with missing screen, it has blown loose and is visible at an angle. It is suppose to be out of sight farther up at the top of the precat, but because it has blown loose, you can see it in the picture.
    --------------------------------------------------------------------------------- - - --------------------------------------
    Q. "You mean the hollow in the cat unplug pics DSC06098-100 is all that the exhaust gas needs to move out?"
    A. No, that is the SECOND CAT hollowed out. I needed to hollow out the second cat because it became totally plugged up. Your first priority is to hollow out the FIRST CAT (the pre cat), that is where the problem arises that destroys the engine. Your second cat is probably ok If the second cat is not plugged, I would recommend that you leave it alone. Only hollow out the SECOND CAT if you need to.
    --------------------------------------------------------------------------------- - - --------------------------------------
    Q. "The engine looks new and clean for a 73,000miles car so I was wandering is this not one of those the engine has been worked on and sent to Nigeria?"
    "Since you said the engine is good when you had a look at it,will you recommend it for somebody? since every car has its own fault."
    A. The Nissan 2.5L I4 engine is a very good and solid engine design. The basic engine is very reliable, the only problem was this exhaust systen flaw that was messing up some of the engines, and the root cause of the whole thing is that the computer was allowing a slightly too rich mixture in the exhaust, which in turn causes the deterioration of the pre cat. The real solution is to have the computer memory "reflashed" or "upgraded" to eliminate the root cause of the problem. But on a used car, it is also good to hollow out the pre cat because it is likely that damage to the pre cat is already being done, and that damage to the engine is likely to follow, if something is not done about it.
    --------------------------------------------------------------------------------- - - -------------------------------------
    Q. "One sunday morning,about 2 months ago, I started the Car and after some seconds i heard a sound like something has dislodged inside the bonnet and i thought it was the cat since I have read several reviews of it coming off and damaging the engine.I was already looking foward to the engine dying but the noise stopped as if the stuff has dislodged and off we drove to church and till now nothing has happened.I change the oil every 3months with 4litres, and the filter every 6months and the oil level remains the same."
    A. Over here we have "Hoods" instead of "Bonnets". You could have the second big problem that those engines have, the "Butterfly valve screws coming loose and getting sucked into the engine" I have not had this problem yet. When I had my daughters engine apart, the screws were still tight. These are also called "Power Valve" screws, they are located inside the INTAKE manifold. Two small screws hold each butterfly valve onto the shaft, there are 4 butterfly valves (one for each cylinder), total of 8 screws. There are know to come loose and fall out. when they do, they have no place to go but get sucked into the engine. Once in the engine, they bounce around inside the clyinder, and can cause much damage, or if you are lucky, maybe not to much. It is just a matter of how the screw happens to bounce around in the cylinder, before finally getting blown out past the exhaust valve. The bouncing screw can bend or break the spark plug, score the clyinder walls, crack the head, crack the piston, or crack or bend the valves or valve seats. To fix these, the intake manifold has to be removed, then the screws removed and then cemented tightly back in place or cement new screws back in place.
    --------------------------------------------------------------------------------- - - -----------------------------------
    Q. "I change the oil every 3months with 4litres, and the filter every 6months and the oil level remains the same."
    A. I would suggest that you change the oil filter at each oil change. How often you change oil depends on the miles, type of driving, and road conditions. Idling is harder on the engine, as well as dusty roads. Our Altima is driven in mixed City and Highway on clean roads, so I change oil and filter every 5,000 miles, using high quality Mobil One Synthetic Motor oil 10W-30 and a Purolator "Pure One" synthetic motor oil filter. 5,000 miles works out to be about every 4 months for us. It gets a new air filter every 15,000 miles and an Automatic Transmission Fluid Flush every 60,000 miles.
    --------------------------------------------------------------------------------- - - ----------------------------------------
    Q. "Is there a way of knowing if the pre cat has been removed? Do they remove it before sending the cars to Nigeria?"
    A. The only way to know for sure is to pull the exhaust pipe loose from the bottom of the exhaust manifold and look up inside and see if it is there. It is most likely that yours would still be there.
    --------------------------------------------------------------------------------- - - ----------------------------------------
    Q. "When I bought the car, the service engine light was on and I complained because of the reviews I read on the net about it.Later since it was not giving any problems and many cars down here show that, I ignored it.I changed the oil and filter, it still remained but after taking it out on a journey of about 500km I noticed the SES light has gone off.It remained off until about 3 mths later when it came on.I always turn the fuel cap several times after refuelling.I serviced it again ie changed the oil,the light remained.Now I travelled again about the same distance as the previous one and noticed that the SES light has gone off again(2weeks ago), and has remained off till now.My question now is can one use the light to gauge when to change the oil?"
    A. The check the SES Light, you need to read the codes with a Code Reader or Scanner, or have them by someone. Once you know what the code is, you use logical thought and mechanical skill to determine what the problem is and how to repair it. There are a lot of codes and it must be diagnoised properly.
    --------------------------------------------------------------------------------- - - ----------------------------------------
    God Bless
    E.D. in Sunny Florida, USA
  • PART TWO of TWO
    Q. "You know this car so much that If I were in your position, I will erk out some living from it."
    A. I don't need anything from this car. I have a good job at an engineering firm. I Only got so involved with this one because it is my daughters car, so I do all that I can to help her. I have worked on cars all my life, I've always been a car buff and motorcyle buff. I have worked as a professional mechanic in my younger days, but I retired from that. I still do all my own work on all my cars because I don't trust others, I do better work than them, I know exactly what is done and document all my work with paperwork and photos. My reward comes from having very reliable vehicles to drive (I have 3) and helping others, like you.

    God Bless,
    E.D. in Sunny Florida, USA
  • ndiboyndiboy Posts: 36
    Thanks a lot once again and God bless you!!1 for all the information.Well we make do with what we have down here.We dont have all the big gadgets for the diagnosis and thats why one needs to be careful because all the mechanics do here is mostly trial and error.
    One more clarification,the car drives rough especially especially the owners side when it enters pot hole.It also shifts as if its gonna stumble when it enters pot hole.Is this a stabilizing rod or shock absorber problem? as i am already planning on getting one for a change.
    I will keep the pics and show my mechanic what to do as i dont want him to mess up the stuff.
    Thanks once more.
    Chuma.
  • ndiboyndiboy Posts: 36
    Hi, Ed, is it normal for the fan to be working intermittently? This is what my Altima does and is even more pronounced when I use the A/C and the noise increases like a vibration.
    When the car is started, the fans does not come on until the temp is in the middle of the temp gauge, are all these normal because my Maxima and Blue bird's fan blows all the time.
    Chuma.
  • "Hi, Ed, is it normal for the fan to be working intermittently? This is what my Altima does and is even more pronounced when I use the A/C and the noise increases like a vibration.
    When the car is started, the fans does not come on until the temp is in the middle of the temp gauge, are all these normal because my Maxima and Blue bird's fan blows all the time."

    See my messege #154 in this forum, I explain the operation of the fans. The fans come on when the coolant temperature reaches about 202 to 203 degrees F, and the fans turn off when the coolant temperature falls to about 188 degrees F.
    Good Luck
    E.D. ISF
  • ndiboyndiboy Posts: 36
    Hi ED, it seems you didnt read the issues I raised on question 291 about the owners side shock absorber/stabilizing rod, please do well to give me an answer.Thanks.
    Chuma.
  • We have had not suspension problems, so I do not know about the problem that you have. I do know that the front suspension uses a McPherson Strut with spring on each side. You may have a problem with it or with loose suspension bushings. About the motor or transmission stubbling, we have not had that problem either, sounds like a low speed engine problem. Like I said before, you need to read the computer codes and do proper diagnosis. If they don't have computer scanners over there, they need to get some, the small handheld scanners work well, they read the codes, tell you what the code is, clear the codes, and also monitor live sensor data, so that you can actually see and read the sensors (you can see the voltage swinging up and down on the oxygen sensor, coolant temp, ignition timing, etc). Once you know the code, you have to use logic or flow charts to figure out how to fix the problem.
    E.D. ISF
  • ndiboyndiboy Posts: 36
    Thanks once more ED.I really need this scanners but then about how much do they cost? Does it come with a code decipher? If they are not really expensive, I will ask my friend in the USA to help me get one when coming home in some months time.
    I thank God I discovered this site now I know much better, though ignorance is bliss.Can the scanners discover reason for low MPG? I am presently getting 18-22.3 in city and 26-31 in free way depending on driving conditions.I have read reviews of people getting 26/35-40 city/freeway and I get jealous especially with Camry and Honda.What am I doing wrong or is it the car?
    Chuma, Nigeria.
  • You can find out all about the scanners, how to use them, and all about the trouble codes (DTC'S) on the internet, simply Goggle "automotive scanners".
    Some of the top ones are:
    Autoxray
    Autotap
    Autoenginuity
    Mine is a 2001 model by Autoxray, it was $200 then.
    They now run about $200 and up. They have handheld models, and also have ones that plug into a laptop computer to give all types of fancy displays.
    Research them on the net , and you will find out all about them.
    Also Goggle "OBD II trouble codes" and you will find out all about the trouble codes (Diagnostic Trouble Codes) and how to read and interpret them. The codes do not tell you what part is bad or what part to replace, they point you in the right direction in your search for the problem.
    About your gas mileage, that is a matter of keeping the engine in good tune, to be sure all cylinders are firing properly, to be sure the transmision shifts properly, The transmission torque converter should lock up at cruising speeds, and driving habits play a big part, easy on the gas, keep rpms low when accelerating, and easy on the brakes. If you apply the brakes hard or stop fast, that is moving energy that is lost or wasted (lost gas mileage).
    Good Luck,
    E.D. ISF
  • bcole05bcole05 Posts: 3
    ED,
    Seems like your the one to ask around here so here goes:
    I have a 2.5S with ~90000 miles on it. It burns 1 quart of oil every 50 miles. It doesn't appear that any coolant is getting inside the cylinders and the coolant level stays the same. I took out the spark plugs and in cylinders 2,3,4 you can see deposits and oil on top of the piston. The spark plugs look bad but nothing excessively bad. The car runs perfectly fine and there doesn't seem to be a loss of power. There is blue-ish smoke coming from exhaust as well. The problem started on the trip from FL to MD when the car was heavily loaded. Needless to say, I had to put in about 20+ quarts of oil just to get the thing home (it made it and still runs ok). I have had cylinder misfires. The oil looks really black (and not milky). I did a compression test and all four cylinders read in the 160-165 psi range.

    I was thinking scored walls but compression seems ok to me (atleast not bad enough that it burns 1 qt every 50 miles) and the car runs fine with no loss of power. Next, I was hoping it was only a head gasket but no coolant is getting in the engine (not sure if it is possible for a blown head gasket to leak just oil into the cylinders). So now I'm hoping for bad valves (but seems weird that 3 cylinders would go at one time). I've heard things about the pcv valve going bad but could this be a cause as well?

    Anyway, I was looking for your thoughts. If it is the valves, can they be replaced without having to take off the timing chain and cylinder head?

    Thanks for your help!
    Ben
  • Ben, I'll try to help, but there are other people here to help also. Yes, you certainly do have an oil consumption problem, but it has to be determined where the oil is going. You said you checked the spark plugs on clyinders 2, 3 & 4, but what about cylinder #1? Since your compression is good AND you have no loss of coolant, it would be a safe assumption for now to say that you don't appear to have a head gasket leak. The oil could be entering the cylinders from several locations.
    First, I would check the PCV valve and hose, as a bad PCV can suck oil out of the engine crankcase and into the cylinders. You can temporarily disconnect the PCV and plug the openings and see if that makes any difference after 50 to 100 miles. Also, when the PCV is diconnected, see if you get much smoke (blowby gas) coming out of the hose that connects the PCV to the valve cover.
    You said the oil was very dark, how long does it take to get dark after an oil change? How often do you change your oil? You may need to change your oil more often, but I guess by adding so much oil, it's like a constant oil change.
    Second, the oil can get into the cylinders past worn oil control rings, those are the lower rings on the piston, each piston has 3 rings, from top to bottom, an upper compression ring, a lower compression ring, and an oil control ring. If the oil control rings do not work properly because they get broken, weak or damaged, they will allow oil to leak up past the piston into the combustion chamber and burn with the gas on top of the piston. Since your compression readings seem fairly ok, the walls are likely not scored. Replacing rings ia a major overhaul, having to remove the engine, very costly.
    Third, another thing that can cause high oil consumption is oil leaking past the valve guides, but as much oil as you have to add, it would have to be more than just the valve guides.
    If you need valve work, the entire head has to be removed and the head rebuilt at a machine shop. Have the engine and head checked by a competent machine shop. If you search these messeges you will find that I have went over all of that before and I have posted links to photos of the complete teardown and rebuild of the engine head removal, and head replacement, with links to many photos of it all.
    Forth, another thing that could cause this issue is that the "Power Valve Screws" have a nasty habit of coming loose on these cars and they get sucked into the intake of the engine, and can cause severe damage to the engine, if they happen to take a bad "bounce" before they finally find their way out the exhaust. They can even cause a cracked piston, head or valve. See previous messages about this issue, or Google it.
    Have you had any problems with the catalytic converters yet? Since you are burning oil, that oil goes through the cats and will cause them to fail eventually.
    I would start first with the simplest thing to check, the PCV valve and hose.
    Good Luck,
    E.D. ISF
  • bcole05bcole05 Posts: 3
    ED, thanks for your reply.

    I checked all the spark plugs and they looked ok. Dirty but not excessively dirty. As for the oil, I change it religously every 3000-3500 miles. I have not done an oil change since the problem (figuring I was basically doing one all the time). Before the significant increase in oil consumption it didn't get black right away and the engine probably burned 1 qt every 1000-1500 miles. And then all of the sudden it shot up to 1 qt every 50 miles on the trip home. Now the oil is constantly dark even after adding more. When I pour in oil, there seems to be fumes coming out of the oil port in the valve cover. Not sure if this is because everything is hot, or if this is normal, or if it is exhaust fumes exiting from a busted valve that is being trapped in the valve cover.

    From my understanding of what you wrote, it is possible to have a bad oil control ring but still have decent compression. Is this correct and do the rings usually fail all at the same time or could just one fail?

    I have not had problems with the precat or cat yet. However there are codes that are stored and I will be borrowing a friends code reader tonight to see what they are. Since I had to add so much oil, I am already planning on having to replace the cat and the precat (but either hollowed out or with a header) assuming the engine can be fixed for a reasonable amount of money.

    I guess my plan of action now is to check the codes and see what they say first. I will try to replace the PCV valve and hope that fixes everything. Then I would like to take off the exhaust manifold/precat and see what the inside of that looks like. If theres nothing left, I would expect the problems to be much worse than feared. I was also going to take off the valve cover and look around, but will I really see anything from just doing this? Next, I was going to check out the intake manifold and see if all the butterfly screws are still there (I am assuming thats the same thing as the "power valve screws").

    Do that seem like a reasonable path to take?

    One last question, is there any reason to take it to the dealership do you think? The car and exhaust components are out of warranty (~90000 miles) and since I have a code reader and already did the compression test, I don't want to pay for someone to tell me something I already know. I am figuring that since I don't have oil reciepts, a maintanence history through Nissan (I do everything myself), and the car is out of warranty, I will have no chance at getting Nissan to help fix/pay for anything.

    Thanks again,
    Ben
  • ndiboyndiboy Posts: 36
    Dear ED,
    Thanks for all the contribution so far, its been wonderful joining this forum.I have indeed learnt a lot from you guys.
    My exhaust pot has two outlets and I normally check the gas coming out of it.I noticed that the pipe to the right from the back blows out cold air while the one to the left blows out hot air.Is this normal? just a chance discovery by putting my hand there when i start it in the mornings.
    I also want to find out the meaning of PCV valve and hose and where they are situated in the engine.I am a doctor and the PCV I am used to is 'Packed Cell Volume'.
    Now I know better I am afraid to travel with this car, Ignorance they say is bliss, but knowledge is still supreme so I want to learn more and more.
    Thanks to electricdesign (trying to figure out the name or guy name).
    Thanks, Chuma.
Sign In or Register to comment.