1991 Pontiac Grand Prix engine wont start

Tiny
RJP1948
  • MEMBER
  • 1991 PONTIAC GRAND PRIX
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 131,000 MILES
Have replaced all sensors and a new wiring harness from the fire wall to the radiator, Have fire to the plugs, Have 44 to 50lbs of fuel pressure. Code reads 12 so ecm is good as it is brand new also. New icm as well. Changed the prom over also. Will try to start for a second and then quits. Have had a dia mach on here but no codes other than 12.
Thursday, March 19th, 2009 AT 9:21 PM

1 Reply

Tiny
MMPRINCE4000
  • MECHANIC
  • 8,548 POSTS
If fuel pressure is good and you have spark, hook up a noid light to injector connector to see if ECM is pulsing injectors. If not then check injector fuses.

Also try spraying starting fluid down throttle body, if engine runs for a few seconds, then fuel issue, otherwise an ignition timing issue (crank sensor for example).

In addition to spark and fuel, you need compression to start, so check compression with mechanical gauge.
Was this
answer
helpful?
Yes
No
Friday, March 20th, 2009 AT 6:51 AM

Please login or register to post a reply.

Related Engine Not Running Content

Car Cranking but Not Starting? Try This
VIDEO
Car Cranking but Not Starting? Try This
Instructional repair video
Engine Not Starting
GUIDE
Engine Not Starting
Over the past 20 years at 2CarPros we have identified the top problems that are easily fixed. This guide can save you a trip to the repair garage or calling a tow truck and...
VIEW MORE