Evap Leak(s)

[sleepery]

I had the check engine light come on in my 1999 Explorer and smelled fuel inside the vehicle . It was two P0442 "small evap leak" codes .
The shop said there was one leak in the rear of the vehicle and one in the front . They changed the canister and the EGR valve .

This got rid of the fuel smell but the 2 codes came back in about 10 days . I took it back in and they said it was a loose hose on the canister and returned the vehicle to me without the engine light on . The light came back on with the same two codes a week later .

I am looking for a different shop to diagnose this any ideas of what can be done to fix the issues ?

 

[Whipcitywrencher]

You may want to check or replace your gas cap.
Iv'e gotten an evap code with a bad gas cap.

 

[sleepery]

Thanks Pete .I replaced the gas cap with a Motorcraft cap and it only turns about an inch before it stops and has no "click" to it . I read that this was normal but it feels like it needs to be tighter . I also sealed the fuel filler neck and around the perimeter of the gas cap area . I cleared the codes and they are now pending . I'm curious to see if this at least takes care of one of them .

 

[Linctex]

The rubber parts are nearing 20 years old.

It could be ANY rubber part in the system - in any location.

Good luck finding the leak.

 

[sleepery]

Not a bad run for the age of the truck and I am pretty sure there will be more leaks to come . I just saw a video of a guy who used a home made smoke machine to put smoke into the lines and visually detect leaks . It was pretty interesting and not that technical .

 

[2strokeNorthstar]

Crawl under and look. My F150 evap hoses are turning to dust. No idea why. Get some silicone vacuum hose on eBay and start replacing any suspect sections. My F150 light never comes on but Evap is NEVER ready. Over 1 year of driving. Oh well.

 

[bdcardinal]

Funny you mention this because I just had a check engine light come on on the 2014 Mustang. Dropped it off at service since to have them look at it for me and it had a P0442 code for a small evap leak. The tech rolled out another one of the tech's parts cannons and replaced the purge valve on the intake manifold and the fuel filler neck. The Mustang has the capless fill so any leak in that area you have to replace the filler neck. It was covered under emissions warranty so I had nothing out of pocket.

 

[mattd]

Purge solenoids are extremely common with late model fords across the board for some reason.

 

[bdcardinal]

Originally Posted by mattd
Purge solenoids are extremely common with late model fords across the board for some reason.


I sell a ton of them. We had the purge valve in stock but the filler neck was overnight.

 

[zzyzzx]

Check for rotted evap vacuum hoses.

 

[HangFire]

Originally Posted by sleepery
I had the check engine light come on in my 1999 Explorer and smelled fuel inside the vehicle . It was two P0442 "small evap leak" codes .
The shop said there was one leak in the rear of the vehicle and one in the front . They changed the canister and the EGR valve .

This got rid of the fuel smell but the 2 codes came back in about 10 days . I took it back in and they said it was a loose hose on the canister and returned the vehicle to me without the engine light on . The light came back on with the same two codes a week later .

I am looking for a different shop to diagnose this any ideas of what can be done to fix the issues ?

I went through a similar journey with my Dakota. Replaced gas cap and two hoses on charcoal canister, cleared codes, codes (large and small evap) came back, cheap cracked 6 month old Dorman hoses on charcoal canister got replaced with Mopar, cleared codes, codes came back.

Did serious debugging on the PWM signaled solenoid, finally satisfied myself that it worked perfectly. While I was doing that, the codes cleared themselves (first time ever) and haven't been back since. Only things I can figure is either a.) it deeply respected my electronic debugging ability or b.) the solenoid contacts needed a bit of burnishing.

 

[tomkat22]

Yeah it's probably gonna take a smoke machine to find it. I'd call a few shops and ask them what smoke machine they have and how "successful" they've been when using it. Scanner Danner has a good video on youtube where he has trouble tracking down a pesky evap leak.