P0420=Catalyst System efficiency below threshold
Check your universal joints for wear.
Trouble code P0446 means:Evaporative emission control system vent control circuit malfunction
Check Coloradofans.com or 355nation.net. Both are leading Chevy Colorado message forums.
I have an 06 Colorado and there was a recall on them for that. Might be something to check into.
How do you reset check engine light for the 2009 Chevy trail blazer?
The spark plug gap for a 2004 Chevy Colorado with a 3.5L engine is typically set at 0.040 inches (1.0 mm). It's important to check the specifications in the owner's manual or service manual, as variations may exist based on specific engine configurations. Always ensure the gap is correctly set before installation for optimal engine performance.
You must have an engine scanner to do that.
You can either bring it in to a Chevy dealer or use a programmer/tuner to reset the check engine light.
check crankshaft sensor sensor
It requires an engine scanner to do that.
check this site out
Check