Fuel Evap Nightmares

2010_impala1

I have a 2010 Chevy Impala and have had the engine light come on so many times because of the fuel evap code.

I have had the code reset so many times. I have had 2 new gas caps and multiple servicing. This is getting ridiculous.

Anyone else have this problem?

Mr_Shiftright

Should be fixable. Are you working with a qualified mechanic? Do you remember the exact code you are getting.

The EVAP has multiple parts so there are any number of possibilities here.

thecardoc3

Mr_Shiftright said:

Are you working with a qualified mechanic?

Obviously not. A qualified technician would correctly analyze a failure in this system in one try.

Mr_Shiftright said:

The EVAP has multiple parts so there are any number of possibilities here.

Whether there is one failure, or multiple issues the right way to test this system is with a scan tool that can perform bi-directional commands. "IF" the code is a component or circuit code, then direct diagnostics of the affected component need to be performed. If the code indicates a system performance or a leak code, the scan tool is used to command the system to pull the tank and canister into a vacuum and seal the it while the absolute pressure is monitored. From there sections of the system can be isolated until the one with the leak is identified.

There are variations from these initial steps that must be taken as one drills down to the solution, no two failures should ever be assumed to be the same thing until after each had been proven by following a correct routine.