My son has a 2007 Kia Optima 4 cylinder with a couple hundred thousand miles. It's due for the CA smog inspection, but has the CEL on. Codes are P0455 (large evap peak) and P0451 (evap pressure sensor range).
Our first reaction was to replace the gas cap with a new Stant. No luck, code came back on. So we took it to a local mechanic with a Yelp good reputation. They said they did a system pressure test and found no leaks. So they replaced the gas cap again, this time with a new OEM unit.
A few days later the codes are back. We called the mechanic and they basically said they will just throw parts at it until it gets fixed. Not very cost-effective for us.
I do all of my own routine maintenance and even the occasional timing bet and clutch, etc. but have never attempted to solve an evap problem.
In an attempt to avoid going back to the mechanic, do you have any suggestions on how I repair this myself? My research tells me that if it's not the gas cap, it's either the purge valve solenoid, charcoal canister or pressure sensor. Only the purge valve solenoid is easily accessible on this car. How can I more accurately pinpoint the problem?
Our first reaction was to replace the gas cap with a new Stant. No luck, code came back on. So we took it to a local mechanic with a Yelp good reputation. They said they did a system pressure test and found no leaks. So they replaced the gas cap again, this time with a new OEM unit.
A few days later the codes are back. We called the mechanic and they basically said they will just throw parts at it until it gets fixed. Not very cost-effective for us.
I do all of my own routine maintenance and even the occasional timing bet and clutch, etc. but have never attempted to solve an evap problem.
In an attempt to avoid going back to the mechanic, do you have any suggestions on how I repair this myself? My research tells me that if it's not the gas cap, it's either the purge valve solenoid, charcoal canister or pressure sensor. Only the purge valve solenoid is easily accessible on this car. How can I more accurately pinpoint the problem?