Engine shut off while driving

1997 GMC C3500
176,000 MILES • 7.4L • V8 • 4WD • AUTOMATIC
Avatar
GEERTZE
  • MEMBER
  • 2 POSTS
while driving truck shut off. cranks but does not start. It has 65 lbs fuel pressure and spark, no codes. would a crank or cam sensor cause this? I did try a different ECM and checked all the fuses.
Jan 26, 2018 at 12:59 PM
Advertisement
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
Good morning.

Did you put the original PCM back into the truck? Does the check engine light still work with the key on?

When you crank the engine does the tachometer move up a little showing rpm reading?

Also, remove one plug and check the compression. lets make sure the timing chain is in time.

Roy

Jan 27, 2018 at 4:31 AM
Avatar
GEERTZE
  • MEMBER
  • 2 POSTS
not the original PCM and yes the tachometer does move a little. I will check the timing.
Jan 27, 2018 at 7:18 AM
Advertisement
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
if the tachometer moves while cranking, the crank sensor is working.

the swap on the PCM, did you have it flashed to your truck? it needs to see the VIN from your truck to properly work.

Roy
Jan 27, 2018 at 7:41 AM