2006 Jetta black smoke and no power...bad EGR

[artificer]

Just wanted to post about the bad EGR in my Jetta. Over the last year it was losing power and smoking more. Mileage went down as well. I was told it was probably a boost line leak, but that wasn't the cause. Ended up being a stuck EGR valve. At the end the engine hardly started, would knock when revved, and made a big cloud of black smoke.

I decided to replace the EGR instead of trying to clean it. (230K on the engine) Engine is running better than it has for the last year. I'll eventually clean the old EGR, and see if it still works. If it does, I'll have a spare to use.

The car has a stage 1 Malone tune with dynamic EGR. Bigger injectors were installed during the head replacement. (pump bolt came loose and took out the timing belt at 183k) The dynamic EGR tune was used to hopefully make the 2nd replacement EGR cooler last for the rest of the cars life.

Hope this post can help someone diagnose their problem in the future.

Michael

 

[aj164]

My mpg is down 10-15% in the last couple of months. The VCDS turbo test checks OK. The car starts often slightly rough - like it fires, misses a few beats, and then fires and turns normally. I plan to check the intake and the EGR.

 

[nord]

Understand that your EGR valve is a two-part affair. You have the mechanical side, Either side can be a problem. In my case it was the sensor side. The sensor was reporting a correct setting to the ECU but the valve was actually not being actuated properly. So... No CEL but poor starts, smoke, and only at the last stages a total failure.

VAGCOM will be your savior as you'll see what's happening in real time. By this I mean you may detect the smoking and poor performance while diagnostics still seem to say all is well.

Shut the valve and disconnect the electronics. You'll set the CEL but your engine should begin to run well. This will confirm what you already suspect.

 

[BPatrick]

Understand that your EGR valve is a two-part affair. You have the mechanical side, Either side can be a problem. In my case it was the sensor side. The sensor was reporting a correct setting to the ECU but the valve was actually not being actuated properly. So... No CEL but poor starts, smoke, and only at the last stages a total failure.

VAGCOM will be your savior as you'll see what's happening in real time. By this I mean you may detect the smoking and poor performance while diagnostics still seem to say all is well.

Shut the valve and disconnect the electronics. You'll set the CEL but your engine should begin to run well. This will confirm what you already suspect.

Hey Nord I know this is a very old post. I am currently 14 hours from home blowing black smoke with no power and popping noise. Almost exactly symptoms described above. I attempted unplugging the egr but it made no difference. You say to close the valve, how do you do that manually?

 

[Mozambiquer]

Hey Nord I know this is a very old post. I am currently 14 hours from home blowing black smoke with no power and popping noise. Almost exactly symptoms described above. I attempted unplugging the egr but it made no difference. You say to close the valve, how do you do that manually?

With the popping noise it is very likely a failed camshaft that is your problem, not the egr in your case. Pull the valve cover off and look for a worn camshaft lobe.

 

[BPatrick]

With the popping noise it is very likely a failed camshaft that is your problem, not the egr in your case. Pull the valve cover off and look for a worn camshaft lobe.

While I do not discount that it could be a camshaft, it occurred rather suddenly, plus the popping only occurs after about 1800 rpms (whne the turbo starts to kick in?) There is no knocking when running below boost rpms but I have a lack of power and a hard time getting the car up to speed. I also have thick black smoke and there was some smoke in the cabin which has me confused because i cannot identify where it is coming from. Currently stranded in Texas lol.

 

[Vince Waldon]

Yeah, all of a sudden sounds EGR-open-a-hair-and-unmetered-air-screwing-things-up.

By any chance do you have your VCDS with you? Best and easiest way is to cycle the EGR using VCDS... it will often close itself eventually.

If you have the tools to pull the EGR you might be able to wiggle it closed (or at least confirm that it's open a tad) but it tends to jam internally (actuator mechanism gunks up with soot).

 

[BPatrick]

Yeah, all of a sudden sounds EGR-open-a-hair-and-unmetered-air-screwing-things-up.

By any chance do you have your VCDS with you? Best and easiest way is to cycle the EGR using VCDS... it will often close itself eventually.

If you have the tools to pull the EGR you might be able to wiggle it closed (or at least confirm that it's open a tad) but it tends to jam internally (actuator mechanism gunks up with soot).

I do not have VCDS with me. My plan is to remove the EGR valve and see if it is gunked up tomorrow AM and also inspect the cooler for any breaks or other issues that may explain smoke getting into the cabin. If I am able to identify issues with the EGR cooler, is there a reason why I can't just get the valve closed and unplug it removing it from the system? Appreciate your help.

 

[Vince Waldon]

Yup you can pull it, hold it up to the light to see if it's leaking a bit, and then, if you can wiggle it closed, reinstall it and leave it unplugged. You'll throw a code of course, but the least of your worries at this point.