05 Passat BHW MAF/not MAF issue

rpatricky · January 14th, 2019, 16:45

Hello everyone. I have lurked here for a long time learning and researching and using the information to modify and fix my 05 Passat BHW TDI and really appreciate all the knowledge provided by this community.

The car has 314,000 miles and balance shaft conversion has been done.
Original turbo
No loss of power on acceleration
Uses about 1/2 quart of oil at 6k on the oil changes

Now...on to my dilemma.
So...my car developed a studder in the idle when in park or stopped in gear. It is producing white unburnt fuel out the exhaust until I add throttle and a MAF code appeared (now I cannot remember the number).
I unplugged the MAF and it idles smooth and doesn’t blow white smoke at idle anymore. Needless to say I replaced the MAF, plugged it in and back to rough idle.
Below is a list of everything I have had done since replacing the MAF.
New EGR installed
New seals and clamps on all Boost pipes (7 in total)
New tandem pump
Valve cover gasket (leaking at the time)
Checked cam lobes and were smooth with no noticeable wear.

The oil cap dances like crazy when unscrewed from blowby produced from somewhere?? Thinking if it were rings I’d have more oil loss...

Any ideas on what else I should be looking at/replacing? I am at a loss here and appreciate any and all input.

rpatricky · January 16th, 2019, 10:18

Think the MAP sensor could have anything to do with it or maybe the new MAF is bad?

oilhammer · January 16th, 2019, 10:33

What is the actual vs. requested MAF values at idle? Any coolant loss at all?

rpatricky · January 16th, 2019, 10:45

I’m not sure and will have to take it back to my friends shop to get that information. No coolant loss at all.
Is there anything down by the turbo I should be checking?
If it were injectors wouldn’t it stay at a crappy idle with MAF plugged in?

This whole thing is perplexing me and is frustrating. I appreciate the help.

oilhammer · January 16th, 2019, 10:54

No coolant loss at all would rule out a leaking EGR cooler, so that's good.

Next step is scan tool. Shotgunning parts at a car without making use of the OBD that is already there will become an expensive and time consuming endeavor.

rpatricky · January 16th, 2019, 11:07

Yeah. I know. I’ll get it to the shop when I am able and will reinspect the cam as well. From all I am reading I find it hard to believe at over 300k miles it isn’t worn somewhere.

oilhammer · January 16th, 2019, 11:29

I have PD engines with over 300k on the original cams through here all the time.

rpatricky · January 16th, 2019, 11:52

Good to know. Thanks