Question about 1990 Chevrolet C1500
High CO and HC at idle means in most cases that the catalytic converter is worn out, also very contaminated engine oil can cause this as well as factor's like the engine running cold due to a faulty thermostat, so replace the thermostat, change the oil if needed and replace the cat converter and it will most likely pass, my experience? 35 years as a Class A smog inspection and repair technician at a GM dealer.
Posted on Jul 21, 2010
a 6ya Mechanic can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need.
Posted on Jan 02, 2017
Tips for a great answer:
May 26, 2014 | Cars & Trucks
Mar 05, 2013 | Chevrolet C1500 Cars & Trucks
Jul 31, 2009 | 2002 Toyota Camry
Jun 03, 2009 | 1989 Ford Ranger
Apr 14, 2017 | 1993 BMW 3 Series
Jul 16, 2008 | 1990 Ford F250
496 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: