MarkChai

Sequence of events:

I pull into work, in my new(er) B6 Avant USP, and I go over this ridge into the parking area and bottom out without scraping (I realized that I wouldn't clear since the car is lowered so I stopped) I hit the horizontal part of the downpipe and the surrounding ?subframe? just behind the front wheels, but not too hard; no dent in the downpipe or anything. I pull in and go to work. I'm not even sure if this has anything to do with what happens next.

After work, I take a buddy in the car for a spin to show it off. I wait until the temp rises at least halfway to middle, and then take off: 1st, 2nd, 3rd, stop (short blocks in that part of town). I do this three times and don't go more than 5,000 rpm.

I stop the car and we switch seats without turning the car off. He goes about half as aggressive as I, but I notice the turbo spooling sound is replaced or masked by more of a louder "SHHHHHHHHH" sound. Car starts running rough, gets worse, and stalls almost immediately. We try to start it again. Every time it turns over and starts fine, but in 2-3 seconds it starts running rough and dies in about 2 more seconds, even if I give it gas... That seems to make it worse. And the exhaust smells REALLY BAD, maybe rich? not sure. Not normal tho'. I try about 7-8 times and give up.

I let the car sit for about 30 mins, it starts right up, and I rev it at about 3K for a minute or so, let it idle, all is good. I put it in reverse, give it gas, and hear the "SHHHH" sound again, car runs rough, and car dies, whether I give it gas or leave it alone. Game over.

I visually inspect all hoses, exhaust manifold and exhaust connections from above. It looks ok, but it was night time. I'm going to go to work tomorrow, jack it up, borrow a VAG cable and see what's up.

Any ideas?
Specs: '04 USP Avant, 1.8T QM, Milltek exhaust, car is under warranty. (edited)

Merkin

boost leak, might of broke something on the bump

Dewm

Coil packs!

Tgr_Clw

Post up the codes once you pull them.

MarkChai

...BTW - one of the replacement coil packs was bad, and the way the car ran when the bad one was installed was a true cylinder missing. What is happening is not a cylinder missing, it seems to be either too much or to little of (a) air or (b) fuel. If I give it any more than gradual throttle, the car chokes.

Tonight I moved the car to a spot with more light since it's sitting at work, and while I was doing that the ESP indicator light come on for a few seconds while the engine was sputtering and I was moving it around. Weird.

Hopefully I'll have codes for y'all tomorrow. Thanks for the interest!

MarkChai

OK, I had a chance to get the car towed home. Below are the codes, which primarily seems to indicate a faulty MAF, but there's more going on than that. Are these things covered under warranty? Thanks to anyone who can help.

Mileage: 65810km/40892miles
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Address 01: Engine Labels: 06B-909-518-AMB.LBL
Component: 1.8L R4/5VT G 0003
Coding: 0016711
3 Faults Found:

17535 - Fuel Trim; Bank 1 (Mult): System too Rich
P1127 - 002 - Lower Limit Exceeded - Intermittent

16490 - Manifold / Barometric Pressure Sensor (G71) / (F96): Implausible Signal
P0106 - 008 - Implausible Signal - Intermittent

16487 - Mass Air Flow Sensor (G70): Signal too High
P0103 - 001 - Upper Limit Exceeded - Intermittent
Readiness: 0000 0000

-------------------------------------------------------------------------------

Address 03: ABS Brakes Labels: 8E0-614-517.LBL
Coding: 04275
Component: ABS/ESP allrad 3429

1 Fault Found:
18265 - Load Signal: Error Message from ECU
P1857 - 35-10 - - - Intermittent

-------------------------------------------------------------------------------

Address 17: Instruments Labels: 8E0-920-9xx-8E2.LBL
Part No: 8E0 920 950 P
Component: KOMBI+WEGFAHRS. RB4 D42
Coding: 01229

1 Fault Found:
00562 - Sensor for Oil Level/Temperature (G266)
30-10 - Open or Short to Plus - Intermittent

diagnosticator1

and see if the same codes re occur. The oil level/temp sensor is located on the bottom of the oil pan, and may have been damaged by the incident.
The other DTC, refers to the barometric pressure sensor located inside the ECU, if that DTC reoccurs, the ECU may be bad. The warranty will cover random failures otherwise.

B56

underneath, remove belly pan and check it out.

Your mass air sensor is tweaking out cause there is no suction from the turbo.

Your manifold pressure is off because you have no boost.

Your running rich cause the ecu is spitting more gas but the extra air from the boost is not their to compensate.

I bet you popped that hose!

MarkChai

Only Two: Same MAF code, and a new one below it that makes no sense to me. I'm going to take a look at that turbo hose per Bs6x.

Address 01: Engine Labels: 06B-909-518-AMB.LBL
Part No SW: 8E0 909 518 AK HW: 8E0 909 018 A
Component: 1.8L R4/5VT G 0003
Coding: 0016711

1 Fault Found:
16487 - Mass Air Flow Sensor (G70): Signal too High
P0103 - 001 - Upper Limit Exceeded - Intermittent
Readiness: 0110 1101

-------------------------------------------------------------------------------

Address 46: Central Conv. Labels: 8E0-959-433-MAX.LBL
Part No: 8E0 959 433 BB
Component: Komfortgerát T7B 1411
Coding: 12140

1 Fault Found:
01366 - Opened Due to Crash Signal
36-10 - Open Circuit - Intermittent

diagnosticator1

I popped a DV hose once and the engine would not run with that DV hose disconnected, It would start but die immediately.