A Few Evaporative Emissions System Questions


2004 Chevy Trailblazer P0455
My truck has a check engine light on the dash. We had the computer scanned for codes. It comes up evaporative emission (EVAP) control system large leak detected (gross leak).
I think the number was P0455. What is causing this problem on my truck? I heard it could be just a bad gas cap. How do I know if that is the problem?

Chevy Monte Carlo Several Evap Emissions Codes
I WOULD LIKE TO KNOW WHAT EXACTLY DOES CODES P0440 and
and P1440 MEANS. The check engine light is on and the mechanic said the problem was in the EVAP evaporative emissions system. Can a code like this cause my car to not start or is it just that warning light?

Pontiac Vent Valve Code
Why does my car HAVE A CHECK ENGINE LIGHT on. IT IS FOR P
0449 EVAP control system. I CHECKED THE VENT SOLENOID AND IT IS TURNING ON AND OFF. COULD THE SOLENOID STILL BE BAD? WHAT ELSE SHOULD I DO? Maybe a wiring problem or a bad PCM.


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Dodge Catalytic Converter Causing Engine Over Heating
My Dodge is overheating. The engine light is on. Can a plugged catalytic converter cause this problem
since my truck has had an EVAP code stored in the computer for a long time.  I tested the TPS, replaced radiator and thermostat but that did not fix the problem.

Ford Explorer Rough Idle Engine Misfire
My Ford idles rough, has a flashing engine light and a misfire. I have read a flashing light can cause the catalytic converter to fail
and that would be a very expensive repair. If that is true what can be done to fix my car at minimal cost for parts and labor?

Grand Prix P0420 Keeps Coming Back
We have replaced the catalytic converter several times on my car and the engine light keeps coming back on with code P0420 catalyst efficiency low. I have also changed the spark plugs, fuel filter,
ignition coils, intake gaskets and many other parts.
Does the oxygen sensors effect the emissions
control system and cause this problem?


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