Truck Won't Restart After Shutdown
 

Ok this problem has been going on for a while...it finally threw a code today, P0302, here is the link to the explanation:

http://www.obd-codes.com/p0302

We took it to sears auto center about a year ago after we got the code the first time and when they diagnosed it they said everything was fine, but obviously it isn't...

Here is what has been happening lately: on short trips the car seems to not want to start after being driven a short while. on trips where she is at one spot for a while (school, work) it starts fine after sitting, but if she drives to the store down the street and runs in real quick the car won't start. today on her way home from work the car was vibrating real bad and the check engine light came on so she went straight to auto zone and got the code scanned and now the car is still sitting there because it won't start again. now we can go back in about an hour and it will start just fine. any ideas from that list on the link?

Thats a missfire code. Probably a coil or a bad plug. Less likely an injector. So when it wont start are you saying it wont turn over at all? if so you need to check the conections the firewall relay and less likely the starter. My guess is the firewall relay is bad. From the sounds of things anyway. The code is definitly unrelated to the no start issue.

If it turns over but wont start its a fuel system problem. Fuel filter pump or regulator.

It will crank just won't run, until it cools down for about an hour, then fires right up. I'm thinking it's electronic, not mechanical. Maybe the ignition pick-up or module, like the internals of a distributor.

sounds like its the fuel pump to me.

Update?

My thoughts are a fuel delivery issue or clogged catalytic converter. When you turn the key on, but don't crank the engine, can you hear the fuel pump come on? If not, check the fuel pump relay before looking to replace the pump. Do you get a rotten egg smell from the exhaust? If so, willing to bet it's a problem with the cat(s).

My vote is coil. I had a dirt bike that had a crack in the coil you couldn't even see,ran like a rocket til the coil got warm. Found out that when the coil warmed up it caused condensation inside the coil and shorted it out, it was like trying to start it without the plug wire on. If you have the coil tested it will probably show as being good because it will be cold.
Next time it won't start check it for spark, bet you'll be suprized!
Good luck

One bad coil will cause a misfire code but not prevent it from starting.

Thats right there are 8 coils and ignition system on these engines rarely have complete failures that cause no start situation. My bet is fuel system the op needs to check fuel pressure and diagnoses the fuel system first.

x2:thumbsup:

If it was a fuel problem, I think it would give him trouble anytime and not just on a warm restart? I'm thinking ignition, maybe the crank pickup or the module that is used to send the signal to the COPS to fire on start-up is heating up and then stops working.

This is a friends truck and he hasn't been back to the site yet, scarperformance.com/forum/viewtopic.

Its easy to eliminate fuel by checking fuel rail pressure while cranking. If pressure is within limits then problem is with spark or air. However injector control circuit could also be a problem, but unlikely.

Check air intake.. common problem with some filters is to come apart and clog air intake. Might also look for big vacuum leaks.

If air and fuel are ok, then that leaves you with spark/ignition.

I agree with that it would most likely be a fuel system issue. I had a similar problem with my '97. It would crank and crank and crank but not start. This problem was not all of the time though. It would work occasionally and once it was running it was fine. Changed the fuel pump and filter and the problem disappeared immediately.

Your crank no start issue was that only on warm restarts or cold and warm starts?

Had the same problem you did, and I did'nt believe, like you, that a fuel pump could be intermittant.

Turned out to be a faulty fuel pump