2000 A6 2.7t acting up to the extreme
#1
07-23-2012, 10:20 PM
2000 A6 2.7t acting up to the extreme
Hello,
I have a 6spd 2.7t a6 quattro, i love the car...when it runs right.
My problem- CEL came on (this problem seems intermittent), car is down on power, runs rough at idle (sometimes), sounds like its overboosting, the top of my intake box (mating pieces) seems to pop off at times as cause the car to run a muck. I've had a similar problem to the point where it was almost undrivable, i found that the turbo in piping on driver side was popped off, all is good now, but it is a similar sensation when driving/at idle. I've replaced the plugs, air filter, mass air flow sensor and poked around here and there. Knowing just how many things it can be i'm hesitant at self diagnosing this... I ran a VAGcom scanner and got general codes of the vehicle running rich in a bank, and a or multiple misfires.
So here's what i think
1. bad diverter valves?
2. torn throttle body boot?
3. clogged catalytic converter
4 bad o2 sensor(s)?
5. any ideas?
PLEASEEEE help, i'm getting tired of losing races to rice burners :,(
Thanks ahead of time
I have a 6spd 2.7t a6 quattro, i love the car...when it runs right.
My problem- CEL came on (this problem seems intermittent), car is down on power, runs rough at idle (sometimes), sounds like its overboosting, the top of my intake box (mating pieces) seems to pop off at times as cause the car to run a muck. I've had a similar problem to the point where it was almost undrivable, i found that the turbo in piping on driver side was popped off, all is good now, but it is a similar sensation when driving/at idle. I've replaced the plugs, air filter, mass air flow sensor and poked around here and there. Knowing just how many things it can be i'm hesitant at self diagnosing this... I ran a VAGcom scanner and got general codes of the vehicle running rich in a bank, and a or multiple misfires.
So here's what i think
1. bad diverter valves?
2. torn throttle body boot?
3. clogged catalytic converter
4 bad o2 sensor(s)?
5. any ideas?
PLEASEEEE help, i'm getting tired of losing races to rice burners :,(
Thanks ahead of time
#2
07-24-2012, 08:27 AM
AudiForums WilkommenVagen Direktor
Join Date: Jan 2010
Location: Western MD USA
Posts: 2,955
Willkommen to the forums!
I think you are on the right track with your line of thinking. flashing CEL, running like crap/rough are all signs of misfires. does your scan indicate a single misfire point, or the random multiple misfires? if the O2 or the CATs were causing your problem they would trigger their own codes and probably not give you as much trouble as you are noticing. my opinion is that you are definitely having an "air metering" issue. since you have replaced the MAF, the next most likely cause is a leak somewhere. check for vac leaks, or the easiest thing to do is just replace all the vac lines as leaks are notoriously hard to spot. a torn TBB is also a good possibilty, as it is a weak point on the 2.7T. most often the TBB tear is not really noticible. when the pressure in the TBB increases, it opens the tear a bit and that is where you have problems. DVs are also a possibility. they are easy to get to, so pop them off and see if the diaphragm is blown (put a finger over the vac port and hold it in your palm to block off the other port, stick your finger in the remaining port to depress the diaphragm, let the air out around your palm and then close it off, if it sticks to your palm the diaphragm is ok, if it wont hold that suction it needs to be replaced). finally, check your plug gaps. if you just replaced the plugs out of the box without gapping them, that could cause your misfires. last but not least check your ICM modules. they are on top of the air box. bad ICMs will also cause misfires (there is one ICM for each bank. if your misfires are all isolated to one bank but not the other the ICM for that bank is a good possibility)
I know it seems like a lot but it is definitely DIYable. use the search function if you get stuck, or post back. you may want to post in the A6 section, as you are likely to get more views/competent help there
good luck
-not an expert, just an enthusiast
I think you are on the right track with your line of thinking. flashing CEL, running like crap/rough are all signs of misfires. does your scan indicate a single misfire point, or the random multiple misfires? if the O2 or the CATs were causing your problem they would trigger their own codes and probably not give you as much trouble as you are noticing. my opinion is that you are definitely having an "air metering" issue. since you have replaced the MAF, the next most likely cause is a leak somewhere. check for vac leaks, or the easiest thing to do is just replace all the vac lines as leaks are notoriously hard to spot. a torn TBB is also a good possibilty, as it is a weak point on the 2.7T. most often the TBB tear is not really noticible. when the pressure in the TBB increases, it opens the tear a bit and that is where you have problems. DVs are also a possibility. they are easy to get to, so pop them off and see if the diaphragm is blown (put a finger over the vac port and hold it in your palm to block off the other port, stick your finger in the remaining port to depress the diaphragm, let the air out around your palm and then close it off, if it sticks to your palm the diaphragm is ok, if it wont hold that suction it needs to be replaced). finally, check your plug gaps. if you just replaced the plugs out of the box without gapping them, that could cause your misfires. last but not least check your ICM modules. they are on top of the air box. bad ICMs will also cause misfires (there is one ICM for each bank. if your misfires are all isolated to one bank but not the other the ICM for that bank is a good possibility)
I know it seems like a lot but it is definitely DIYable. use the search function if you get stuck, or post back. you may want to post in the A6 section, as you are likely to get more views/competent help there
good luck
-not an expert, just an enthusiast
#3
07-24-2012, 02:42 PM
Awesome thanks man i'll give those a try. I also didn't point out, the CEL is solid, and i have had multiple codes, p0300 which was multiple misfires, and running rich in a bank. I beleive it is air related because of how similar the car runs to when i blew my driver side turbo intercooler tubing off. I'll look into buying a new TBB, would a torn TBB throw these codes?..and also make the car run like absolute crap? If i could explain just how its running, it's as if there's almost a cut under acceleration, not any single type of acceleration either. Every so often it will jerk when i try to give it the beans, it's just about undriveable (i dont want to damage anything). Also it sounded as if it was overboosting before/when the CEL came on, not sure if it's compensation for lack of oxygen? Not sure, and yes i've been reading around, if i had a guess i'd agree with vacuum lines/torn TBB, or some other air delivery piping..something along those lines
Also like to add, before i threw these last codes, i had another episode with the CEL/poor vehicle power/response/idle
The codes were, p0103, p1127, p1129, p1137, and p1139 (dang that's too many).. but seems as if theyre all connected. I'll make a copy on the A6 thread board. Thanks for the help i really do appreciate it, just trying to get my baby up and running.
Also like to add, before i threw these last codes, i had another episode with the CEL/poor vehicle power/response/idle
The codes were, p0103, p1127, p1129, p1137, and p1139 (dang that's too many).. but seems as if theyre all connected. I'll make a copy on the A6 thread board. Thanks for the help i really do appreciate it, just trying to get my baby up and running.
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