my truck will only run if the check engine light is on

1989 CHEVROLET TRUCK
155,000 MILES
Avatar
JMKASINGER1
  • MEMBER
  • 1 POST
the truck will start fine, but if the check engine light dosn't come on it will die within 10 seconds. but if the check engine light comes on and stays on it will run all day, but it runs very rich when light is on.
Jan 12, 2012 at 6:17 PM
Advertisement
Avatar
JDL
  • CAR REPAIR CONTRIBUTOR
  • 16,098 POSTS
How long since a tune-up? Any applicable trouble codes? You may need to check voltage and grounds at computer?

If it refuses to start, do you have spark, engine cranking? If you have spark, check fuel pressure and injector pulse.
Jan 12, 2012 at 7:03 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.