Check Engine Light and Engine Misfire on Audi Q7

Problem Description and Possible Solution

An engine misfire may be noted after cold start resulting in illumination of the Check Engine Light. Our technicians tell us updated powertrain control module (PCM) software is available to correct this concern.

Problem Data
RepairPal Verified
Average mileage: 84,800 (45,000–155,974)
Exhaust & Emissions affected: 3.6L V6
3 model years affected: 2007, 2008, 2009
40 people reported this problem
Viewing 1 - 15 of 15 comments
Car bucks and shudders after cold start and at times when it is warm as well. I have been to the dealer three times. They put an Audi gas additive in it, claimed fuel in New England was poor. It happened again shortly. Brought it back in again, they tried the additive again and told me aggressive driving would cure the problem. It happened again shortly after the additive. Brought it back again, this time for intake valve cleaning, new spark plugs, and new coils. After 5 or 6 days, went to pick it up. Service rep went to get the car, started it up, CEL came on and it stopped running. Can you believe that? Now I am waiting to see what happens next. Must be a flaw in engine design.
The engine misfires when cold. Took if the the Audi dealer and was told it was due to carbon build up engine valves. We have only been using Chevron 93 octane fuel. They want to charge $1390 to clean the valves, which is ridiculous. This seems to be a common problem with this model. Buyer beware!!!!
Cold start, engine idles rough for about first 30 seconds. If I attempt to drive during this time car jerks and check engine light blinks. Audi dealer says nothing is wrong. Only solution I have is to let the car warm up until the rpm's stabilize.
Faced with the same problem with misfire. Fault codes: P0300, P0301, P0302, P0304, P0305, P0306. These codes are for cylinder misfire.
At odd times 7 at low RPM (below 3000), the engine struggles to stay at stable RPM - the tach shows the RPM going up and down. When driving there are no issues.
Told the dealer about this some time ago; they blew me off as no problem found (perhaps there was no fault code). Ran Chevron Injector cleaner - no effect. Now contemplating what to do next. Help!
Car hesitates donw entire length of 4 blocks. Engine light comes on, I've taken it in to shop at least twice. They can't replicate problem. Light stays on for longer now, but goes off occasionally. Weird!
I believe I am experiencing the same problem as everyone else on this thread. Engine misfire codes on three cylinders, check engine light would come on, car would buck, rpms would bounce when accelerating from a cold start. Seems intermittent but frequent, with the only pattern being that it happens after starting the vehicle. Took it to local mechanic. They changed all the spark plugs and cylinder coils, ran injector cleaner through it, confirmed I was only using premium fuel. Problem seemed to get better for a few weeks, but is now doing the same thing again. Hoping there is a simple fix, but it is sounding more like this is a flaw with the design.
3.6 L gas--The CEL comes on--Error code indicates a crankshaft timing issue. Misdiagnosis by Audi dealer and then engine has to be removed and multiple sensors replaced. Cost $8000
Same deal as those here; engine light turns on and off back and forth so many times it makes your head spins. stays on for few weeks or days, leaves for roughly the same timeframe and comes right back. rpms surge when sitting at red light. rpms shudder and shake when just turning car on (still in park) - sounds rough especially for first 15 sceonds. noticed aggressive driving (not feather footing the gas at low gears) helps the engine catch and rev smoothly. its when im coasting at low rpms that the misfiring occurs. replaced spark plugs and sensors; no change. At my wits end, at least I'm not alone.
check engine light on. codes reading ,misfires and camshaft position sensor,replaced sensor codes still present engine not misfiring
After cold start low speed driving results in erratic RPM's and jerk/surge (mainly at speeds at/under 20 mph) problem has cause CEL to come on once with random misfire codes present. Cleared codes, CEL hasn't come back but surging is still present.
engine misfires after cold start. taken to dealer twice. Audi says need fuel injector cleaner and/or new injectors. only runs poor after cold start.
Engine stumbels and acts like it wont take throttle after cold start up. Cold start up meaning when car hasnt been driven for overnight period.

Brought the car to Audi dealer initially having received Recal notice on engine misfire. Explained to dealer that the car has some form of misfire and that it stumbles after cold start up. Dealer Tech immediatley asks what grade fuel we're using. Response:93 Octane. Tech asks are you using a fuel additive. Response; No. Tech suggests that issue is a result of carbon build up on engine valves. Now have used Techron for the last 4,000 miles. No change in performance. Car still stumbels after cold start up.