1997 Chevrolet Cavalier No-Start After Stop Fix

it's a performance problem.
The code p0300 means :cylinder misfire detected (random).
begin with the easy checks first.
check base ignition timing;a timing that is retarded by 8 1/2 degrees indicate the valve timing belt has jumped one teeth.
next, check fuel pressure, low pressure can indicate a worn regulator, faulty fuel pump, you did replace fuel filter allready,or damage fuel line.
Now you can do the compression test.
start with the dry compression, if that fail then proceed with the wet compression test.
come back here with the result so we can find out what is wrong with it.

I did forget to include that after the wires and fuel filter were replaced the service engine soon lite has not come back on. When the car is running it runs as good as it ever had. It seems to me that if the timing chain slipped it would never run good.

I can make the tests that were described but fail to see the relevance of anything except the fuel pressure and even that doesn't sense based on the fact that I can duplicate the problem whether the engine is cold or hot. Can you explain the reasoning behind the timing and compression test.

The code p0300 means :cylinder MISFIRE detected (random).
you said your engine runs rough.
If the rings or valves are not seated and allow compression to leak pass them. power to push the piston down is loss.In addition, the ability to compress the air/fuel mixture properly is also lost.if one cylinder has loss of compression,there will be a complain of a " MISS".
The result will be loss of power, poor fuel economy.
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Correct valve timing is importance for engine performance, and I have explained that allready.If the timing jumped only one tooth.
check also for plugged or restricted exhaust system, faulty coil,
if you fail to see the relevance,you can do what you feel if good to get your car running.

good luck

Hi Steve, If you are not familiar with the location of the powertrain control module (computer), it is in the passenger wheel well area in front of the wheel. When you find it, you need to first get a good look at the connector before touching it so you know how it is positioned. Then see if it is tight. Also get a good look at the computer itself, especially the seam around it. These were a problem for water intrusion and especially problematic in the "road salt regions". GM offers a protector that should be installed for future problems ( I'll send you the list of cars that qualify). The bad part is, they don't cover the computer. I don't know that this is your particular problem, but I v'e seen this happen on others like yours. There is one other suggestion that may help. The intake valves can get a carbon build up, doing a variety of mis-deeds. If there is a significant build up, it can impede air flow and reduce effiecient fuel burning. I "think" the various air intake sensors adjust for the air flow, but the fuel problem is different. The build up on the valves:

and on the piston head will get dry from the heat of combustion. When this carbon dries it will act like a sponge, sucking the fuel into it as it enters the combustion chamber. Anyways, try this as good maintenance: Try what I call an air induction service. I like to use castle hydroblast. You spray it into a vacuum line such as the brake booster line if nothing else is accessible. Full spray for 3 minutes, stall the engine with it or have someone kill it while your spraying. Let it set for a few hours then take for a short drive in low gear, revving the rpms to help break it up. First use Castle cleansrite to clean the throttle bore. Try to get the throttle plates scrubbed good with a brush, while your spraying. Use a rag to wipe the carbon out between brushings. Seafoam is another good product, but smokes a lot. http://www.seafoamsales.com/motorTuneUpTechGas.htm http://www.castlepackspower.com/Pages/training/hitech.html IF you can't find Castle, here is my rep's email: robw@castlepackspower.com

Thank you again paul.

I haven't had enough time to really work on the car but have been able to determine that when it is not starting I have spark but I don't hear the fuel pump run for the normal few seconds when the key is turned on.

Based on that I was wondering if there is anything electircal except the fuel pump that could cause intermittent no fuel pump running when the key is turned on.

Thanks again for all the help.

Did I mention PCM?
If you are not familiar with the location of the powertrain control module (computer), it is in the passenger wheel well area in front of the wheel. When you find it, you need to first get a good look at the connector before touching it so you know how it is positioned. Then see if it is tight. Also get a good look at the computer itself, especially the seam around it. These were a problem for water intrusion and especially problematic in the "road salt regions".

I removed the PCM and all connections to it were tight and it doesn't look like any water has damaged it. There is no evidence of corrosion on any of the connectors or inside the case.

What would be the best bet now, pursue having it tested or go for the fuel pump?

Is the dealer the only place qualified to test the PCM if it can't be ruled out yet?

You don't have to go to the dealer. An independent can be located by contacting the local snap-on tool rep, if you are unsure where to go. www.snapon.com.
It may very well be the pump, but wouldn't jump to that conclusion. You could see if power gets to the pump to verify or eliminate it. You can swap the relay with one of the same to see if it starts.

You can half-assed test the pump by rapping on the bottom of the tank while someone cranks the motor to see if it starts. That usually indicates a pump is bad.

Here is the followup on the problem: Everything is fine after replacing the fuel pump. They sure fail in a very flakey hard to troubleshoot way. And if the dealers weren't casking $525 for the part it would be easier to give it a try. I hope the after marked one I found at $255 will last a few years.

Thanks for all the help.

you're welcome :)