No boost issue 05 BEW 17036/P0652

Wanted to share my recent issues with no boost and my findings to help others. initially a code of P0299 turbo under boost showed up which I could clear with the vag-com and the engine would produce boost again. After a couple weeks of this the boost never came back and this new code showed up and would come back immediately after a reset: 17036/P0652/001618 - Sensor Reference Voltage B: Too Low. After a search here it is apparent that plenty of others have had the same issue and there is good information on the subject. I followed the advice and checked the usual suspects, hoses, vacuum lines vnt rod movement etc, all looked fine. The turbo is a vnt-17, and a Kerma tune, replaced about two years ago. After reading a post where someone suggested unplugging the vnt sensor to see if the boost returns I gave it a shot and sure enough it’s back! After closer inspection of the plug, crud is visible. This is surprising because it is an all weather plug which was also replaced about two years ago, welcome to New England driving. After driving 20 miles the cel has extinguished as well even with the plug still unplugged. Maybe the Kerma tune is doing that? Not sure. I will try cleaning with electric cleaner and retry it next. I wish I had tried the unplugging trick first, could be a quick diagnosis short cut. Thank you to others for their advice and I Hope this helps others

I'm surprised having something unplugged does not throw a code, but I do not know about the Kerma tune.
Are you driving with it unplugged?

Gota ask, what fuel mileage do you get with the Boeing?

Where is the VNT sensor? Is it in the turbo actuator down low?

JB05 said:

Where is the VNT sensor? Is it in the turbo actuator down low?

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I think it is part of the actuator on the BEW engines.

Yes the sensor is built in to actuator on the turbo. Two days of driving great with it unplugged and no cel still. I may drop a line to the tuners to see if maybe the tune itself was designed to disregard the sensor information and bypass the cel?

As far as the Boeing goes, to generalize we figure a fuel burn of 750 gallons per hour. Or somewhere around a gallon and a half per mile+/-

OP, I'm curious to know if the tuner did indeed deleted the sensor function. I installed a Garrett actuator on my Borg Warner turbo, but I now have a constant P2565. Boost is good, but I wonder if I should have just left it unplugged.

I will email Kerma and pose the question in regard to my tune and post their reply.

JB05 said:

OP, I'm curious to know if the tuner did indeed deleted the sensor function. I installed a Garrett actuator on my Borg Warner turbo, but I now have a constant P2565. Boost is good, but I wonder if I should have just left it unplugged.

Click to expand...

JB05 is it easy enough to crawl under the car, disconnect it and see what happens?

No, not really due mainly to the weather. That is why I ask, otherwise I would have tried it.
I contacted a member here, Reference Design, who had a plug-n-play fix for this issue. He said he was going to send me what he
had, but I'm still waiting. I also contacted a Malone tuner regarding a delete, but I think they misunderstood my intentions and told me no.

Have no problem deleting the VNT sensor, we can also rent out tools. Feel free to pm me which shop you spoke with.