Confuzzled!!! Truck dies randomly then wont start... spent 1500 trying to fix.
Truck drives fine one day, then stalls and won't restart the next day. We
have replaced fuel pump (3x), fuel relay, vaper mang. valve, the SPORD
sensor, O2, sensons, crankshaft sensor, battery, checked for ground,
checked anti-theft (no difference) and multiple other things... any ideas?
When cranking- the fuel pump is not getting the signal everytime, but then
randomly it will start and run for hours... HELP!!!
Sound like it may be electrical, when it warms up, Possible coil pick-up (pole piece) or the electronic control module. (ECM)
Seems like the truck is protecting itself by shutting off gas flow...? No recent collisions...
Not saying this is your problem but had the same problem turned out had to replace the harness connector to fuel pump was making a bad connection.
I know you replaced fuel pump & relay but maybe do some checks on fuel pressure, possible fuel regulator or leaking injectors. Verify that there is no problems with the fuel system. The ecm has similar symptoms.
That is a good possibility there firebird...
Cant find ECM in Haynes Repair Manuel... another name?
Mornin all. When the truck wont run you say that its shutting off fuel delivery, does it also not have spark? Is the engine light doing its prove out (on when key cycled/ off when cranking) when it wont start? If it doesn't come on at all then there is something shutting the pcm down. Have you also checked or swapped the pcm relay with another one to rule it out?
Harness has been plugged in repeatedly... no shorts seems to make themselves evident...
Sorry, Ignition Control Module, Has to do with the delivery of the spark to the plugs...took the place of points...
here is a pic
These can be tested at Auto-Zone...
Guy- yes it has spark after it dies... have replaced the relay...
Well looks like that should be enough to keep you busy...
Thanks.... will checkin later...
The thing about a harness connector you can not see inside of it to see if it is not making connection or not and plugging it in and out repeatedly is not going to let you know if it is making connection or not if connection in harness is bad.
And also when I had the same problem plugged it in and out repeatedly did not help until I replaced the harness connector.
If the problem is electronic, as was the case with my 2003, best you bring it to a shop with an electronic analyzer. Took the mechanic all of five minutes to plug the analyzer in, try to start the car, and say the PCM was bad. I was told I could not replace the PCM myself as it has to be initialized and programmed once installed. My repair was between 3 and 400 bucks. Autozone sells the part for around 200.
