I want to delete or bypass the EVAP system in a 2012 Yukon Denali with a 6.2

[spencer60]

https://www.epa.gov/sites/default/files/2020-12/documents/tamperinganddefeatdevices-enfalert.pdf

It is a crime to knowingly falsify, tamper with, render inaccurate, or fail to install any "monitoring device or method" required under the Clean Air Act, including a vehicle’s on-board diagnostic system. Clean Air Act section 113(c)(2)(C). The EPA has criminally prosecuted such conduct (see text box below).

 

[IMDB]

 

[greg vess]

Sick of this useless EVAP system and want it gone or bypassed. Anyone already done it?

I have been through the entire system and replaced all EVAP parts a few months ago and now I'm back to the pump shutting off again. I'm done with this and want it gone, ready to punch holes in the ozone.

I have done it on many LS cars. You have to have a HP tuners and Diagnostic Suite to do it and not have the engine code stay in. In the diagnostic suite you have to go in and make sure all the EVAP codes set to the on position and then check the do not report box. So it has to be in but not report to the computer. That's how you chest the emissions check. If you try to delete it with out the tuner it will throw the EVAP code and will not pass emissions. If you have a friend with HP Tuners to add a other VIN to the system is 100 bucks or he may have purchased unlimited VIN count. That cost and count might have changed since I had mine. It takes about 10 minutes or less depending on the tuners skill level. Problem is once your VIN is entered you might as well have it tuned. It used to be right s 1000 bucks to have one tuned. It's a lot easier with OEM stock configuration because all you have to do is adjust the air fuel ratio throughout the RPM range and adjust the total timing at wide open throttle to where it makes the most power. Paying someone to do that on a stock engine is ridiculous because it only takes one run of the car to get the info you need to make the changes. You really need a good friend with HP tuners that will allow you to only pay for the VIN entry and then make the changes to the EVAP codes. While it's in there you might as well go ahead and adjust the air fuel ratio and the timing to Max power. Since there's no camshaft or other heavy mods being made all the efficiency tables are the same and none of it has to be changed. The tune is simple and very quick.

 

[greg vess]

When I had my Trans Am I modified everything in the engine so I went ahead and stripped all the EGR and evap stuff off of it. Then once you make the changes in the computer your check engine light will go off before you hit the first stop sign. Then at the emissions center their machine will check that they system is on but they can not check that it's not reporting that's how you get by with it the emissions check.

 

[greg vess]

You will still need to run a hose from the driver side valve cover to manifold vacuum. That way you're not blowing off all over the place when you have positive crankcase pressure. It'll just help evacuate the internal engine pressure once the engine's running at higher PMs. You'll see a lot of guys just stick a filter in there and not run the hose through manifold vacuum. But then you'll see a lot of oil collection around that filter. That just makes a mess and a little crankcase pressure is not going to hurt the air fuel ratio enough to make any big difference in performance.

 

[testdepth]

https://www.epa.gov/sites/default/files/2020-12/documents/tamperinganddefeatdevices-enfalert.pdf

It is a crime to knowingly falsify, tamper with, render inaccurate, or fail to install any "monitoring device or method" required under the Clean Air Act, including a vehicle’s on-board diagnostic system. Clean Air Act section 113(c)(2)(C). The EPA has criminally prosecuted such conduct (see text box below).

I guess alot of hot rodders are law breakers then. LOL

 

[41mag]

I guess alot of hot rodders are law breakers then. LOL

Yep, I am sure they do. We used to do all kinds of stuff when I was a teen/young man while hot rodding.
Speeding is law breaking. lol. There are lots of laws broken everyday.

 

[greg vess]

I guess alot of hot rodders are law breakers then. LOL

I took mine off because I took mine to shows and all that mess under the hood look cluttered. No body couldn't tell but me. I think the emissions guys we're a little suspicious when they heard that big cam thumping but their computer said everything was on the level so they couldn't do anything about it. I even had high flow cats as well so everything looked like it was nice and legal.

 

[greg vess]

I guess alot of hot rodders are law breakers then. LOL

Millions!

 

[greg vess]

These days it's possible to throw and check engine light on for a cold air intake. Most are designed not to but it doesn't take much. Headers will definitely do it. Most any mod that changes air flow or AFR will throw a check engine light/ code.