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FIXITMAN, MasterTechnician
Category: Nissan
Satisfied Customers: 17475
Experience:  ASE Master Certified, AA Degree Auto/Diesel Tech
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I have a 03 Nissan Altima 2.5L SE . About a year ago it started

Customer Question

I have a 03 Nissan Altima 2.5L SE . About a year ago it started idling rough when you put it in drive. It has not really gotten worse but now I have started smelling gas sometimes. The dealership cant find anything wrong. They have tested the throttle body, throttle position sensor. MAF sensor, Intake gasket, and just about everything else. Its not giving any codes. It just feels like timing doesn't advance when you put the car in drive. If you turn the air conditioner on it will smooth it out. Ive changed the plugs but have not changed the wires the dealership said they were fine. Also have checked the 3 way going to the converter and this is fine. The car has 75000 miles on it.    Thanks for any help
Submitted: 8 years ago.
Category: Nissan
Expert:  FIXITMAN replied 8 years ago.
HelloCustomer this is a common problem on this vehicle. Nissan has a technical bulletin for it. The dealer should perform an idle relearn in the computer to fix this. The bulletin is shown below. Let me know if you need more help.

EC04-002 Reference:
NTB04-015 Date:
February 03, 2004


2002-03 Sentra (B15)
2002-03 Altima (L31) APPLIED ENGINE:


An applied vehicle has the following symptoms:

^ Engine RPM rises at start and then drops and cannot maintain idle


^ Engine has low/rough idle


^ Engine runs well if the throttle is held open
NOTE: The above symptoms may occur after an ECM reprogram or the vehicle battery was run down (discharged).


^ Conduct the "Engine Running and Warm Up" procedure
^ Perform the "Idle Air Volume Learning (IAVL)" procedure
^ If the IAVL does not finish ("CMPLT"), perform the "Corrected Idle RPM Check". Then, perform the IAVL procedure again.
^ Refer to the Service Procedure for details
IMPORTANT: The purpose of "ACTIONS" (above) is to give you a quick idea of the work you will be performing. You MUST closely follow the entire Service Procedure as it contains information that is essential to successfully completing this repair.
Customer: replied 8 years ago.
This has already been done. Numerous times. The car idles perfect in park - its just too low in drive.(seems like the timing doesn't advance enough when you put it in drive) I have done the idle relearn myself (when I cleaned the throttle body and the dealer has done it twice) The dealership even completely reprogramed the ECM from scratch. When you do the Idle relearn the idle comes down and runs perfect - but when you put it in drive it gets rough. When you give it gas it runs good (except it is a little sluggish) And you smell some gas.

Expert:  FIXITMAN replied 8 years ago.
Does it do this whether the engine is cold or hot?
Customer: replied 8 years ago.
It does it all the time. It gets a little worse when the car is completely warmed up. Its never stalled bad or cut off. (if you take it out of drive -neutral- and then put it back into drive - it kind of stalls a little - just for a second.) You can tell it doesn't have the pep it used to have either. When you hit the gas it has never stalled or run rough. It just seems like the timing isn't advancing like it should when you put it in drive.

Expert:  FIXITMAN replied 8 years ago.
Okay. If everything else checks out fine then I would look into a bad crank sensor. The crank sensor on this engine goes bad quite often and can cause a variety of problems. It can do this without setting any codes.
Customer: replied 8 years ago.
How about the cam sensor ? Or should I just replace the crank sensor first ?
Expert:  FIXITMAN replied 8 years ago.
Both of these sensors fail on this vehicle. The most common cause of driveability problems is the crank sensor though.
Customer: replied 8 years ago.
In the last recall I had done they told me that they had reprogramed the ecu to ignore the signal coming from the crank sensor. Then I have read that it doesn't ignore the sensor it just reads it differently ?? Do you know how this recall worked ( Recall ID# XXXXX)

Thanks for your time
Ill change the crank sensor and see what this does :)
Customer: replied 8 years ago.
one thing I forgot to mention. Its done this for a while now - When the motor is cold - until it gets completely warmed up it makes a loud clicking noise. I always thought it was just the engine being cold, but I think maybe its the fuel injectors clicking. Would this possibly have anything do do with my problem.
Expert:  FIXITMAN replied 8 years ago.
It is common for the injectors to make noise. They would not cause this problem unless they were dirty and allowing too much fuel into the engine. The recall is usually a reprogram only. You are best changing the sensor along with this reprogramming.
Customer: replied 8 years ago.
I had to order the crank sensor so it will be a cpl days before I can get it. I noticed the cam sensor and crank sensor are exactly the same sensor - What would happen if I switched them around ?? Or should I just wait for the crank sensor to come in ?

Also I found the reason for the gas smell. One of the spark plugs was loose - I think they checked the compression at the dealer and maybe didn't tighten it back.

Thanks for your time
Expert:  FIXITMAN replied 8 years ago.
A loose spark plug would definetly cause a problem. As for the sensor, I would not switch them out.
Customer: replied 8 years ago.
I got the Crank sensor this morning. I put it on the car and it still doing the same thing :(

I did some more checking and decided to take the air inlet to the throttle body off & got my wife to turn the key on. When the key is turned on the throttle valve didn't move, I cranked it up and the throttle didn't move & put the car in drive and the valve didn't move, but when I turned the key off the throttle opened and closed. The car did run a lot worse because of the MAF sensor and it give me a code for it - so Im assuming the MAF is working. ( I may have worded my symptom wrong in the first place - instead of idling rough when in drive - it idles like its under a heavy load when you put it in drive or maybe like the motor is bogged down) But when you give it the gas it smoothes out. Seems like its starving for air until you open the throttle some. -- Would this mean the throttle isn't working while the motor is idling in drive ? Is there a sensor on or in the transmission the tells the ecu that the car is in drive and the timing needs to be advanced ?

Thanks again for your time
Expert:  FIXITMAN replied 8 years ago.
The throttle plate should move slightly when in gear to keep the rpms up. The computer should do this. The transmission position sensor is what tells the computer that the vehicle is put into drive. You would need a scanner to see if the ecm is getting this message. You should check one more thing. The variableinduction/power actuator. Make sure it is closed at idle.

Customer: replied 8 years ago.
The variableinduction/power actuator is closed when the car is at idle. I took the intake off the throttle body again and put my fingers on the throttle valve while someone cranked the car and put it in drive. When you put it in drive the throttle clicks but instead of it opening a little to let in more air - it actually closes all the way. So its getting a signal when the car is put in drive, but is seems it is working backwards. What does this sound like to you?
Expert:  FIXITMAN replied 8 years ago.
It sounds like the vehicles computer might not be giving the right signal. See what the throttle does when turn the a/c on in park.
Customer: replied 8 years ago.
Here we go - Last night the car was completely warmed up - I took off the intake cranked the car and left it in park, turned on the compressor and the throttle valve did crack just a little so I decided to turn off the ac and put it in drive - this time it cracked the throttle plate just a little just like it did when I turned on the AC(Im guessing it did what it did before because the car was cold )

When the air inlet hose is off the throttle body and you put it in drive - the car bogs down and the motor shakes much the same as it does with the intake hooked up to the throttle body. Except it worse wit hthe inlet off. Ive cleaned the MAF but this MAF doesn't look like others I have messed with. Can the MAF be malfunctioning and causing the car to loose power when driving and bogdown when idling in park ?

Im gonna do a compression check next and pull the intake and make sure all the butterfly valves are in place & no screws have come out and shot through the motor. (I see the Altimas have had this problem in the 2002 - 2006 years)

Thanks again
Customer: replied 8 years ago.
Doing a little more looking and found that when you crank the car up - in park it idles smooth when you give it gas it has no hesitation or anything - when you put it in drive it idles hard (the idle is even, but it vibrates and you can see the motor vibrating more than it should) a few months ago when you had it in drive if you turned on the airconditioning it would mostly smooth it out, but now its slowly getting worse (when you turn on the air it smooths it out but not as much as it did) And the other week it got worse bogging down and almost cutting off when at idle in drive. I put some gas treatment in the tank and cleaned the throttle body and it got better to point that it just vibrates hard at idle in drive. If you have it in drive at a stoplight and put it in Neutral then put it back in drive it almost cuts off. but it doesnt do this from park to drive ? Maybe thats because it has a sec more to respond because it has to go past reverse before you hit drive. Does this maybe sound like the throttle body drive is getting weak or maybe worn and not opening as much as it should ? The throttle response is not a good as it used to be either. It still runs smooth through all the gears and no problems at hwy speeds, but you really have to give it more pedal than you used to. I still keep going to the MAF and Throttle body I just hate to replace both if I don't have to :( I know these sensors work together to make the cars run better and cleaner but thay can be a pain in the butt !!

I also unplugged each coil pack and the engine missed the same in all four cylinders. So its not skipping or anything.

It still feels like its starving for air

Expert:  FIXITMAN replied 8 years ago.
It does sound like you are having a problem with the throttle body or with the MAF or even the accelerator position sensor. The only way to really be able to tell though is with a scanner to see what each is reading. You can try resetting the accelerator position sensor by disconnecting it and turning the key on for 2 secinds, of for 10 on for 2 off for ten and then hooking it back up.
Customer: replied 8 years ago.
I did a compression test on the motor and got these numbers
#1 - 165
#2 - 165
#3 - 160
#4 - 165

I also unpluged the accelerator position sensor and reset it. This didn't do anything different.

I pulled the top of the air filter box off to make sure it didn't have anything blocking the air before it got to the MAF - This didn't do anything.

I cranked the car put it in drive and give it just a little pedal to get the RPMs up and even at 800 - 900 RPM it still vibrates.

If you let off the brake and let the car roll at idle it stops vibrating and runs smooth. Its only when completely stoped - that the motor vibrates.
Expert:  FIXITMAN replied 8 years ago.
Okay. If it is just a vibration then you may have a simple engine mount issue. Besides the vibration, the vehicle will attempt to stall sometimes, correct?
Customer: replied 8 years ago.
The engine mounts have been checked and are like new.

Well it stalls if you have it in neutral and put it in drive (then it acts like the rpm almost goes too low, but this is just for a split second). It never stalls when you press the gas. It never stalls on its on & the rpm stays steady around 600.

You also can physically see the motor vibrating, but it only does this in drive. In park it is smooth.
Customer: replied 8 years ago.
How about the Harmonic Balancer - could this cause this problem ?
Expert:  FIXITMAN replied 8 years ago.
It is possible, but the vibration would usually continue when initially accelerating.
Customer: replied 8 years ago.
I removed the top half of the intake manifold today to check the butterfly valves and found the intake had a mighty lot of oil in the manifold. Could this be causing me problems? All the screws on the variableinduction/power actuator look good - I thought I may pull the screws and put some loctite on them to be on the safe side. I wanted to ask about this before I put it back together.

Expert:  FIXITMAN replied 8 years ago.
I would not mess with the screws. As for the oil, it can cause some problems. Clean out the intake completely. Make sure that your PCV valve is in good shape. If it is questionable then replace it.
Customer: replied 8 years ago.
I found out the dealer changed my oil for some reason when I had it in doing diagnostics a cpl weeks ago (I had just changed it the week before) anyway they put way too much oil in the car - maybe this was the reason for the oil in the intake manifold & it was coming from the pvc valve. This is my wifes car so I don't drive it often, but Had to drive it yesterday and noticed that the car dosen't idle half as bad in reverse as it does in drive. Could there be something wrong with the transmission causing this vibration ? I checked the fluid and its nice and clean and has no burnt odor. I just found it odd that it idles much better in reverse than it does in drive, 1st or 2nd.
Customer: replied 8 years ago.
I decided to do a good check for vac leaks and I sprayed carb cleaner around every hose and intake gasket and can't find any vac leaks. I let it run for a while and put it in reverse and found it really does not vibrate in reverse. Put it in drive and it it vibrates ?? Does this sound like anything to you. Problem in transmission ? Sensor on Transmission ? Is there a seperate sensor for reverse and drive ?