2CarPros - Car Questions & Answers

1999 GMC Other Repair Question


Topics covered: Catalytic converter, Engine, Tire.
Mileage: No information provided.

Asked on August 16, 2011

Catalytic converter on 99 GMC Denali

I just had a cng converstion kit installed on my 99 Denali and now my check engine soon light came on. I took it back to the shop that installed the cng kit and they now say that the catalytic converter needs replaced. This is very concerning to me as I had just had the entire vehicle inspected and saftey and I/M done and it passed with flying colors. Could the cng kit cause the catalytic converter to fail?
Avatar Asked by CJ Swenson

Answer

Replied on August 16, 2011

The only thing passing that inspection proved is that the code hadn't set yet. You might try clearing the code to see if it sets again. If it does, then you'll have to change the cat.

Tiny Answered by Wrenchtech (expert)
14,713 answers provided