Temporary EGR disable

[MkVer]

The short version of a year long story is that my car doesn't like living at a higher elevation. Basically my car will periodically enter limp mode I've narrowed down the culprit to the EGR valve.

I'm wondering if on I can simply clamp/plug the vacuum line going to the EGR valve to prevent it from actuating? A CEL is fine since I'm constantly getting CEL from my car dropping into limp mode. I just want a car that drives fine.

As for a full delete or emission worries. I live in NM and don't have to deal with emissions testing but I'm in the military and who knows where I'll be stationed next, so a full delete isn't an option right now. Besides, the car runs fine everywhere but here.

 

[Greg Roles]

You sure can, but you will need a lambda probe spacer in the exhaust to trick the ECu out of the error code, and to watch your EGT's as the EGR's whole reason is to lower combustion temps and thus NOX formation. I'm about to try my TDI with the EGR and flap mechanism hanging in the breeze, check my euro tinker thread last page. Still yet to see if it works!!

When I just unplugged the EGR and flap earlier on in my tinkering, I got a CEL, and the car didnlt seem to run as well, seemed down on power as bit. But that was all, and I did pull them both at the same time.

 

[A5INKY]

Except there is no vacuum line going to your EGR valve. Your EGR is fully electronic with a stepper motor. A thin block off plate between the pipe coming up from the cooler and the EGR valve body would effectively stop it from working. However the ECU uses the anti-shudder valve as part of the EGR strategy so you might cause other issues than just a CEL when the ECU sees no EGR flow. I am not sure.

BTW, I don't understand how EGR would be causing a limp mode. I have had my EGR so gummed up and leaky that the car was belching black smoke, would hardly run and it did not cause a limp mode.

Do you have access to VCDS, if so what did it have to say?

 

[thirty3]

Do you think if you blanked off the bottom of the egr valve then replace this with i dunno a pipe with small air filter on the end it will throw a code.


So when egr valve opens clean coolish air is getting sucked in and when egr not working it does not matter.

 

[A5INKY]

That would be called a boost leak. The intake is under pressure on a turbo charged car. Only reason the EGR is able to inject exhaust into the intake air stream at all is because the exhaust manifold that feeds the EGR system is under even greater pressure.

Turbos diesels don't suck, they BLOW!

 

[thirty3]

Yes I agree dunno why I asked such a retard question..lol

Is there anywhere you could take a supply of air from to feed the egr....before the maf or is there not enough pressure.

 

[Greg Roles]

I have successfully run a blanking plate in the EGR pipe and a Wayne angle block from Vortex, but any decent angle block would do such as the 42DD one. That successful experiment lead me to this over the weekend, no more EGR at all for me:

 

[MkVer]

No VCDS. OBD scanner is all I've got right now. The latest code to come up was P0404 "EGR Control Circuit Range/Performance" In the past I have also received P0400 "EGR Flow Malfunction" and P0403 "EGR Control Circuit Malfunction"

A basic run down of the problem is the following: I'll be driving down the road at low to moderate load and relatively low RPM, usually somewhere between 2 and 3 thousand RPM. (the problem has occurred at all loads and RPMs only constant is elevations above 5000ft) My ears will be greeted with the sound of a valve "freaking out" this valve is presumably running through full open and close very quickly and repeatedly. The car will alternately surge and lose power. Then limp mode. This all happens in under 2 seconds. Cycling the ignition brings me back to normal. Also, I only get a CEL once in about every 10 events, despite always ending up in limp. I've driven this car up and down the east coast with no problems, within 24 hours of returning to NM and my home at 7000ft the problem returns. Multiple trips during all the seasons, elevations are the only constants.