EGR

[Rudddog]

I have a 2013 Touareg 3.0. We just replaced the EGR and now it’s throwing a code. Slow EGR has anyone had to deal with this before? What is the fix?

 

[oilhammer]

You're going to have to give a bit more information. The EGR is a "system" of various components that all have to work in concert with one another.

What specific DTC(s) does it have?

 

[Rudddog]

The code for slow EGR is P240F

 

[oilhammer]

So, it flagged this DTC, and you replaced.... the EGR valve ? And it did not fix it?

 

[Rudddog]

Yes we replaced the EGR drove it about 100miles then the p240f code came back. Twice

 

[oilhammer]

OK, it likely has a gunked up EGR cooler, could also have a bad or gunked up EGR temp sensor. But first you need to check for any air leaks, on both sides, from where the EGR tube attaches to the turbo, to the cooler assembly, from the cooler assembly, to the intake duct, as well as any charge air leaks from the charge side of the turbo, down around the passenger side of the engine, through BOTH intercoolers, and back up to the intake... and the intake itself of course. Smoke machine works great for this. I'd also look for any signs of soot under the hood on the top of the engine, as that is a sign of a leak. Also check for a misfit air filter lid, a crappy non-OEM type air filter element, or a leak between the air cleaner and the inlet to the engine, including any breather tube leaks.

Essentially what is happening is the ECU is duty cycling the EGR valve, and expecting to see a different in MAF value, and it is not seeing it quickly enough. So ANY leak that would change this calculated value will cause this DTC to flag.

 

[Rudddog]

Thank you