Mechanics

WON'T ACCELERATE

Nissan Altima

I have a 2002 Nissan Altima with the 3.5L engine. It has 75,000 miles. Yesterday it wouldn't start because the battery was dead. I tried charging it but it didn't help. I replaced the battery but now the car will not accelerate when you push on the gas pedal. It idles perfectly and does not throw any error codes when check by an OBDII code reader. If you accelerate within one second after it starts it will surge, idle, surge, idle and then settle into idle. After that nothing happens when you push the accelerator. Does anyone know what is wrong? Is this something I can repair or reset on the car myself? Thanks for your help.
P.S. I may have posted this already. If so, I apologize for double posting it. I donated you your forum before I submitted it and am not sure if it posted. Thanks once again.
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Barbqme2
June 2, 2007.



Have you double checked all wiring at battery? Never heard of that before, try letting it idle for a few minutes, may need to do some kind of relearn

Tiny
Jack42
Jun 3, 2007.
Thanks, Jack.
I let it set overnight. When I started it this morning the accelerator worked like it is supposed to. I drove it and at first it surged but then it settled down and drove correctly. I drove it about 5 miles with no problems. For no reason that I could see it started acting up again. It would surge and then nothing would happen. While it was surging the car would move. When it wouldn't the car would coast. When I checked it with a code reader it gave me a P0733 code. I know what the code means but don't know what causes it. Could this be caused by a failing fuel pump, stopped filter, or is this electronic? Do you know what the next diagnostic step is? Thanks.

Tiny
Barbqme2
Jun 3, 2007.
Try clearing that code and see if it comes back, It is- A/T 3rd gear function. When you said before that the car would coast, do you mean like it was in neutral? This could be related to the trans code

Tiny
Jack42
Jun 4, 2007.
I cleared the error code but it came back. When I said " coast" I meant as if you had taken your foot off the gas pedal or had put the car in neutral. When this happens it's as if the accelerator pedal is not connected to anything. The car idles perfectly but nothing happens when you push on the accelerator. After a period of time (5-10 seconds) the car will accelerate when you push the gas pedal, but only for about one or two seconds. Then it is like the gas pedal is not connected to anything again. I assumed this code was set because of the fuel injection making the transmission do something unusual. Would a transmission problem cause the car to do this? It doesn't act like it is slipping or causing any problems. Thanks for helping me with this problem.

Tiny
Barbqme2
Jun 4, 2007.
This may sound funny. Does your car have a throttle cable or is it drive by wire?

Tiny
Jack42
Jun 4, 2007.
That's a very good question. I don't know. I will have to look.
Something happened last night that may make the parts of this puzzle clearer. I put a new battery in the car over the weekend. Yesterday evening I tried to start the car but the battery was completely dead, drained to 3.78 volts! The top of the battery was covered in battery acid. This car has only been driven approximately 10 miles or less since the battery was installed. Am I correct in assuming that not only is something in the car powerfully draining the battery but that it is also being way overcharged? Would the most likely culprit be the alternator/voltage regularor malfunctioning? In the good old days alternators had diodes in them to keep charging voltage flowing in one direction. When these failed the alternator could drain the battery. Is this still the case in this car's alternator? Is the voltage regulator built into the alternator? Could this somehow be causing the surging problems this car is having? BS

Tiny
Barbqme2
Jun 5, 2007.
Could very well be the alt. If the comp doesnt have theproper system voltage it will freak out and do some very strange things. If it will start, put a meter on the battery to see if the alt is charging, check for corrosion in the cables, could be a bad connection to the main power center

Tiny
Jack42
Jun 5, 2007.
The alternator is charging. When the old battery was connected to it it was charging at something like 17.6 volts. I assumed it was because the battery wasn't holding a charge. With the new voltage the battery was charging at over 14 volts. I did not check it at higher rpms than idle. It is very possible that voltage higher than normal was being read by the computer. Ironically, the car passed the emissions test the day before this happened, so I have a pretty good idea about the time when it was okay and when it failed. It seems that something failed catastrophically, not gradually. Unfortunately I am at work and the car is at home so I can't check further. When I got the car about one year ago I cleaned the battery cables and put dielectric grease on them. They were very corroded then, but there was no visible corrosion on them when I replaced the battery. I think I will change them, just to be sure.

Tiny
Barbqme2
Jun 5, 2007.
HELLO!
This maybe a speculation. BUT. I see this guy have donate. Guess jack is giving his money woth. Heh heh he. Way to go man.
Let me take a shot at this.
HOW BOUT TRU THINKING OUTSIDE THE BOX?
Okay. We need a vac gage and a volt meter.
Now.
- start the car
- stick it in 1st gear and punch ur gas.
If it still hesitate than u can pretty much spend ur time on the engine. If it doesnt. Then start looking seriously on the tranny
- if it response slow
look up the wiring diaggram for signal wire on TPS and MAF. Hook up the vac to manifold and read the signal as u accelerate. Once u narrow the probelmatic area.U should have no problem to take over from there
|Hey jack. How's my low tech suggestion?
Heeeeeee hawwwwwwww

Tiny
Kin chan
Jun 10, 2007.