EVAP system questions

[dross99_si]

Hey guys I recently got the P0455 code on 2007 Tahoe and in the process of chasing down an EVAP leak. Purchased a new OEM gas cap, Purge valve solenoid and vent solenoid with hoses and filtered vent.

Questions:
1. The stock vent solenoid had the vent hose routed up near the filler neck and on the end of the hose was what appeared to be a cap. Strange. The new (I assume updated) vent system has the rectangular open box with coarse foam filter media. Is there some ECM software update that must be done when changing to the updated vent system?

2. The firewall side hose that connects to the purge solenoid in the engine bay had a old brittle white clip that broke when I went to remove the hose. Can anyone confirm that the Dorman 800-032 is the correct replacement part? They're expensive and I don't want to order a set and find out that they won't work.

Thanks in advance!

 

[Doubeleive]

Have you changed the rear one yet? the hose with cap you are referring to is probably part of the rear airshocks (assuming you have air ride), if you have not done the rear one yet the easiest way to do it is unbolt the gas filler tube and pull it down to attache the new one and then shove it back up and bolt it back in. you cant really see the old one up there unless you get under the truck and use a flashlight because the end is way up at the top of the filler tube

 

[dross99_si]

Have you changed the rear one yet? the hose with cap you are referring to is probably part of the rear airshocks (assuming you have air ride), if you have not done the rear one yet the easiest way to do it is unbolt the gas filler tube and pull it down to attache the new one and then shove it back up and bolt it back in. you cant really see the old one up there unless you get under the truck and use a flashlight because the end is way up at the top of the filler tube

Yes I replaced the one in the rear. I believe it's called the EVAP vent solenoid. It was slightly different than the original. New one had the open vent at the end of the corrugated tubing and the old one had a cap. New one also required a small wire harness converter. Our Tahoe is a LT and doesn't have air ride suspension.

 

[Doubeleive]

Yes I replaced the one in the rear. I believe it's called the EVAP vent solenoid. It was slightly different than the original. New one had the open vent at the end of the corrugated tubing and the old one had a cap. New one also required a small wire harness converter. Our Tahoe is a LT and doesn't have air ride suspension.

that must have been a old design then when I did mine on my 2012 it has the same filter at the end of the tube that goes up by the filler, I am pretty sure it wouldn't require any kind of ecm programming, either the code will go away after doing the replacements or it wont. which would mean maybe a crack in the one of the lines or defective replacement parts.

 

[swathdiver]

Yes, there is an updated design and the CEL will go out after so X amount of cycles with it passing the leak test. Unless of course you clear the code.

That assumes that those were your problems! Could be something else like another broken clip on a hose on top of the gas tank. Smoke test is the best way to identify the problem.

I'm currently ignoring a P0442 on mine. Prefer to throw it all in the trash and turn off the sensors/codes in the tune.

 

[zbad55]

No need for any ECM programming when replace the vent line. The box on the hose up by the filler pipe is just a dust filter.

 

[dross99_si]

No need for any ECM programming when replace the vent line. The box on the hose up by the filler pipe is just a dust filter.

Thanks. I was just wondering because my original part had a round cap at the end of the hose and this new one has the vented box with the dust filter.

 

[dross99_si]

So can anyone confirm that the Dorman 800-032 is the correct replacement clip for the EVAP purge valve line under the hood?

 

[dross99_si]

Update:

The EVAP purge valve (behind alternator) fixed the P0455 code. And for anyone wondering the Dorman 800-032 *IS* a replacement for the retainer on the vacuum line that connects to the EVAP purge valve.