Hi scotty i have a 87 chevy v10 with a crank but no start issue i've replaced the ignition coil distributor cap and rotor starter egr valve iac valve spark plugs and cables knock sensor electronic spark control module fuel tank and sending unit fuel filter fuel pressure regulator housing and injectors aswell the vacuum lines and have spark and fuel still have to check compression. My question is why won't my truck run after all that work i don't know what else to do i will be replacing the ignition switch and the engine control module aswell.
@svangurulfur
I've dealt with this issue with the older Chevys an most every time it's the icm. It's the ignition control module under the distributor cap
Fuel and spark eh? I'd check fuel pressure next but wouldn't mess with ignition key as from everything I've learned, ignition switch/security system kills spark and/or fuel pressure. A bad/weak spark due to a bad ICM as Devon mentioned could very well be the cause.
@hillbilly
He says he has already replaced that.
I'm reading he has mechanical ability and no diagnostic experience.
@Larry Reading the same... with that said... always monitor fuel pressure.... been bite too many times! And why I rant on cars not having a pressure sensor on the fuel rail so the pressure can quickly and accurately be gotten off the ODB... would save tons of time and money not to mention breaking plastic stuff getting to the rail fitting....
Scotty could probably answer this question!
So with being said I will give a little advice. # 1 you are taking a super expensive route to repair a car. Since the 80s cars have become more complex. We dont throw parts at a car now.
I bought some kind of Chrysler out of a back yard and brought it home and decided it had a bad fuel pump. Started to replace and could tell someone already did and it was a bad connector on the fuel pump. Fired right up.
When checking fuel you turn on the key and listen for prime( The pump will run a few seconds and cut offf). And see if there is a test port on the fuel rail. It where you hook up a gauge to a pressure tester. It costs a lot less than those fuel injectors you bought. Some dont have the port. You have to rig one then.
Check for spark. They sell these plug looking things that you put the wire on and turn it over and you can see a spark.
Check compression, if compression is at a loss on one cylinder there's a chance it will not start.
On n older one like that check the wiring harness especially where it goes across metal stuff. My 2000 S 10 died on the way home and I worked on it like 5 days looking for the problem . It was an easy fix right on top of the motor where wire loom was missing. OOOOHHHHH Yeak check all your fuses. You can check for power with a test light. You need power on both sides of the fuse.
You can get a data package on Aldata for like 25 dollars for one car or truck with a year of access.
Good luck and don't give up.
