Engine running lean 88 Chevy 454

1988 CHEVROLET TRUCK

MRPEESHY

MEMBER
1 POST

I have a 1988 Chevy 1-ton that has a 454. After removing the exhaust and replacing it with a better breathing dual system with no cat the truck is running lean. The distributor and O2 were replaced and the timing set correctly but the truck runs lean on the road and makes the manifolds glow red. I have tested the EGR and it is working correctly. I have put a vacuum on the egr solinoid and I get no vacuum when the engine RPM is increased. Could this be the problem? What else could make the truck run this lean?

Apr 23, 2007 at 9:20 PM

RASMATAZ

✓ASE Certified Mechanic
75,992 POSTS

[quote:343158e705="mrpeeshy"]I have a 1988 Chevy 1-ton that has a 454. After removing the exhaust and replacing it with a better breathing dual system with no cat the truck is running lean. The distributor and O2 were replaced and the timing set correctly but the truck runs lean on the road and makes the manifolds glow red. I have tested the EGR and it is working correctly. I have put a vacuum on the egr solinoid and I get no vacuum when the engine RPM is increased. Could this be the problem? What else could make the truck run this lean?[/quote:343158e705]

The solenoid should pass vacuum to the EGR when accelerated.

Apr 27, 2007 at 4:53 PM

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