I was driving down a 45 mph road and motor shuddered and quit running. Trying to get information had led me to rebuilding filter head and replacing all rubber hoses. Also replaced cp3. Cranks but no fire. I understand that FICM rarely goes out. Using a snap on scanner I am getting no codes. Very frustrated. Any ideas? Could it be as simple as replacing the batteries or is it the ecm? How can you test the FICM or the ECM? The truck was my daily driver and need it to get to work.
03 Silverado
- Thread starter SoFloJoe
- Start date
What's rail pressure (desired and actual) while cranking? Do you get a clean stream of fuel out of the test port?
checked all fuses and didn't find any blown. any in particular I should look at more closely?
How do you check fuel rail pressure? I do have a steady stream of fuel at test port. I do notice that the primer pump doesn't stay hard.
You would need some type of logging device or data display device like a scanner (SnapOn, Autel etc), EFILive device, or even something like an Edge monitor will at least tell you desired and actual rail pressure.
If the FICM goes, it normally blows the fuse. Check the EDU fuse. If it's good, you can probably assume it's ok
Does it stay hard after pumping it for 10 minutes or so? It will get soft when you crank the engine and that's normal. Sometimes when you loose prime you may have to pump it up and crank it over. Then pump and crank it again. It can take several time before it catches
But I'm not thinking it's fuel related unless you developed a large leak or restriction if it died while driving. Could be any number of things. But as Brad said, you need to see what the fuel pressure is while cranking to see if it has anything to do with it