P0420=Catalyst System efficiency below threshold
Check your universal joints for wear.
Trouble code P0446 means:Evaporative emission control system vent control circuit malfunction
I have an 06 Colorado and there was a recall on them for that. Might be something to check into.
Check Coloradofans.com or 355nation.net. Both are leading Chevy Colorado message forums.
How do you reset check engine light for the 2009 Chevy trail blazer?
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.
A flashing check engine light is an indication of a misfire.
Check
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