I have a 2002 Altima, It turns over but does not crank. I was told computer was bad so I replaced it its still doing the same thing it acts like its getting no fuel can any one help?
The first thing to check is to see if there are any trouble codes stored in the computer memory. Repair as needed as per code stored in memory.
You said you replaced the computer, did you have the computer properly reprogrammed specifically for your car?
The basics of and engine is compression, spark and fuel.
First check for spark at the spark plugs, if you have spark then check for fuel pressure.
If you don't have spark then trouble shoot the problem and repair as needed.
Check fuel pressure, if you don't have pressure then check fuses, fuel pump relay and fuel pump for proper operation.
Try these few suggestions and get back to me when you can with your results.
Thanks for the reply it tries to crank every now and again.The fuel pump is working and it acts like its getting spark also. So now what?
I need more specific information from you on the cranking problem.
Does it sound like a dead battery?
Does it crank over fast or slow?
Does the starter sound like it is grinding like it is bad? The only way to check this out is to see how many amps the starter is drawing (using) to try to start the engine, it is usually about 200 amps before the starter is declared bad.
Do you actually have spark at the spark plugs and fuel pressure that you can actually see with a fuel pressure gauge?
It's just not clear on how the engine is cranking over.
Get back to me when you have more information so I can help you diagnosis the problem properly.
The engine turns over fast and quick like it should even turns like its going to start every other turn over. It has started back firing a little when it turns over. Yes it has enough fuel pressure so thats where Im at if you can help further let me know. Thanks
There is a service bulletin on a no start condition when cold it is:
May 26, 2004
ALTIMA OR SENTRA W/QR25 ENGINE; NO-START AFTER 'COLD SOAK'
It mentions that a starter replacement, Nissan fuel injector cleaner added to the fuel tank and possible PCM reprogramming.
IF YOU CONFIRM
After a 'cold soak',* the engine cranks (turns with starter), but does not start.
Cold soak: Engine has cooled down to ambient (outside) temperature, regardless of summer or winter seasonal variations.
The engine may start if it is cranked for an extended period (more than 5 seconds) or if the throttle is opened during cranking.
After starting and operating for a few minutes the engine runs normally.
Try to start the car with your foot on the gas to the floor, if it starts then go to your local Nissan dealer and have them perform the procedures in the service bulletin I listed.
If the car has high mileage; then check the timing belt. If it has never been replaced the timing belt then it may be worn and could have slipped a tooth on the belt throwing off the valve timing.
Try these suggestions and get back to me when you can, we can go on from there.