Mechanics

MODELS FAILED CALIFORNIA SMOG

1990 GMC Other

Engine Performance problem
1990 Other GMC Models V8 Four Wheel Drive Automatic 246000 miles

I just failed CA smog, my HC levels are as such
Idle- RPM- 1062, HC measures 173
2500 RPM- HC measures 400

What should I do to correct this? Truck seems to run fine.
Thanks
Avatar
Linvdan
August 19, 2008.



At that mileage, it could very well be the cat converter is all used up. They are a reactive material and will only last so long

Tiny
Jack42
Aug 22, 2008.