I have a 2012 RAV4 with the 4cyl that generates an EVAP error. We did the easy thing and replaced the gas cap with an OEM cap clearing the errors and off we went. 2 weeks later error returned, and I went to the mechanic for a smoke test and the results were indeterminate (no leak). The best suggestion was "replace everything" This means the purge valve (up by the air cleaner) and the canister assembly, at $1300 (including labor) this is a pretty hefty price. It has a mere 91,000 miles so it may be worth it. To add to the mystery, I put some old fashion Seafoam in the gasoline and the error disappeared. This has happened a few times with this car. I get a check engine light, give a gas treatment, the light goes away, and the error is gone (as in not scalable). Any magical thoughts? Being from MA, emissions matter. Eventually, this will catch up with me at inspection time. Should I just bite the bullet and replace everything? I might wait till spring and do it myself as crawling under the car in frozen MA is tough on this old timer.
Thoughts?
Never use Seafoam in an automobile engine. It is made for 2 cycle outboard engines only. What are the code(s) it is showing?
Don't just throw parts at it figure out what's wrong and fix it or just leave it as is
the smoke test was not done correctly.
it should be used together with a bidirectional diagnostic tool
I am a bit absent-minded and I lost the piece of paper that I wrote the code on. It was a minor EVAP leak. That is why the gas cap was replaced. The code was cleared, it came back 2 weeks later, and was smoked tested with inconclusive results (no leak found). The code went away (CEL turned off) 3 days after the smoke test and it returned last night (CEL came on about 7 days after it turned off). I need to go put the scanner on it and this time I will try not to mess up my notes.
The local mechanic that did the smoke test and ran his scanner is not sure it is worth putting the money into the car and given his solution of replacing all the main components, I am not sure he is convinced that it will fix it. I am looking for a smarter solution. The hoses that I can see look fine.
As for the Seafoam, it is what I have around for my old snowblower. The old Tecumseh likes its Seafoam.
The code is P0456 as of 8:00 AM EST.
The code disappeared yesterday. The CEL went out and no codes are pending. Based on the silence, I guess I should start replacing parts and hope for the best.
Well, I had the canister and purge valve replaced. So now it has a new OEM gas cap, a new canister assembly, and a new purge valve. Just two days later and the light is back on. Either the new parts are bad or the smoke test was not done correctly. The other options are a line that has a true leak (start replacing lines), a bad filler neck, or a gas tank leak.
- I live in MA too! That damn emissions lol. Ok I have a Hyundia with that same code. Just about replaced everything myself and it pops on and off every couple of months. This is what I do to pass emissions… after clearing codes the evap monitor is the last module to become ready. Ma lets you pass with one module not ready. The evap monitor can only get ready if fuel level is at a certain point. For my car it’s after 30 percent so I clear the codes if they are present before taking the test. But I make sure my gas level is below quarter tank. I run the car below quarter tank for about 250 miles or so. I connect my scan tool and look for how many modules are complete. Once the evap is only one left I go get my car tested and it passes every time!
