2012 CC Lux +, 123,000 miles, DSG 2.0T
Had a crap weekend. Car stalled on me while rolling through a toll booth on my way into work. EPC light and flashing CEL came on, car ran very rough (like it was missing). Pulled off and shut it down, let it sit for a minute and then restarted, ran like a champ, no more lights. I let it idle for a few minutes and nothing else happened so i headed off to work. Checked for codes later and of course nothing since the CEL was not lit (I do not have a VAGCom cable, just a basic ODB-II reader).
Fast forward to Sunday, I did a quick bit of maintenance that was due: oil and filter, air filter, basic inspection. I checked the seating of all the coils but did not remove any. Car ran great, nice and smooth. I was going to pop the timing chain tensioner inspection cover off, but opted not to do so until I have a replacement cover, not wanting to potentially create an oil leak if I damage the old one...I do not know at this time if I have the new or old style tensioner, but plan to find out before my motor grenades itself.
Ran my kid home to his Mom's house and started my trip home (130 mile round trip), about a quarter of the way home I was cruising around 40mph and it started missing again, EPC and flashing CEL. I made it to a pull off and tried the same reboot the car procedure to no avail. The car would crank and crank but would not fire. Had my code reader with me still so I checked the codes, now getting P0100 and P0303, so MAF and misfire on #3. I unplugged the MAF and tried again, still cranks but would not start. I could smell unburnt fuel around the car so I opted to stop trying, not wanting to also damage my cat by filling it with gas.
Got a ride home, went back the next day with a trailer, tried to start it, still no fire. Loaded it up, got it home and tried to start it on the trailer, it started to cough a bit and after a moment of cranking it caught, ran like crap for a minute like it was still missing and then it smoother right out and I was able to back it off the trailer and drive it into the garage, now running normally.
Pulled the codes once more this morning and I still have an active P0100 and P0303 and a pending P0303. I have no problem replacing the coils, they've got at least 50,000 miles on them, likely quite a bit more than that. MAF is easy enough to replace too, maybe I dislodged something in the air tube when I was cleaning it and one of the wires got damaged. But whats troubling me is that it wouldn't even fire at all, which it definitely should with one bad coil...but it was acting like it had zero spark. My first thought was maybe my timing chain tensioner went, but I've got no racket coming from the motor and it did start and run smoothly later...I can't believe the chain could slip out of proper timing and then later pop back in. Also wondered about carbon buildup, if it might be giving me air intake valve problems, but again I'm not buying it...I've had none of the cold start symptoms people talk about and again, it did run and only was throwing the #3 cylinder misfire, no others.
The dying and no start while hot behavior is acting very much like my Saab and my friend's 03 Passat did when he had a bad crankshaft position sensor, and that would neatly explain the no start and now starting and running smoothly issue...I had the same sensor go out on my 04 Saab as well. Are the 2.0T motors prone to CPS problems? Other people have this issue?
So, wondering if others have had similar issues and how you conquered them, also wondering what are the optimal coils and new plugs I should be installing on my car...its 100% stock, no mods and I have no intention of modding anything, its just a daily driver. I'll assume OEM for the MAF and CPS if I buy those?
Thanks in advance.