|Username||Post: failed emissions|
05-01-12 06:14 PM - Post#2221300
My 94 Silverado C-1500 5.7tbi w/auto trans just failed emissions. I live in Mesa, Az.
HC is 2.48 standard is 1.60 fail
CO is 14.79 standard is 20.00 pass
NOX is 5.29 standard is 3.00 fail
The truck runs well. It is driven daily 120+ miles round trip to work.
I have noticed a slight miss when the engine is completely warmed up when I come to a stop. The oil pressure dips as well. This doesnt happen all the time.
The exhaust fumes indicate that it is running a bit rich. No smoke!
Havent had a decline in gas mileage or any burning of oil. It has 141,000 miles. It had 116,000 when I got it last June.
At that time the dealer had tuned it up, wires, cap, plugs.
A local shop said it was the cat. Looks to be the original.
Any suggestions would be appreciated.