Audi FSI Engine Carbon Build-up Megathread

[rmh]

Got the vehicle back from the dealer this afternoon - 6 hours from drop off to pickup.
I wonder if the techs are getting experienced at this? Six hours to get the car checked in, serviced and test driven, plus my 45 minutes to pick up the vehicle seems pretty quick.

Driveability is back to where it was when new. For some time now, I noted a pregnant pause hesitation when starting out in first gear when cold, but didn't think anything of it, after this service it appears to be gone. Car feels like its got its spunk back too.

TSBs 2019948/3 (case 2 - case 1 previously performed) and 2020645/5 (ECU update) performed - this included new software for the ECM, removing the intake manifold, swapping injectors, manual cleaning of intake valves and both lower intake manifolds/banks (tech noted "heavy amount of carbon buildup"), an oil service (change) and a test drive per the TSBs.

All service today performed under warranty.

Data Point information: My normal commute since owning this car has been 20-25+ miles each way (when I do not telecommute from home) with road trips every 3 months (600-1200 straight through miles each way, stopping only for gas/restroom breaks), and a number of High Speed Driver Education/track events. I live in the upper midwest where we have cold snowy winters and hot humid summers, but my commutes are purposefully outside of the rush hour so as to avoid stop and go traffic. I consider my normal driving style spirited.

[mattlqx]

I'm not sure how much easier/more accessible the V6 intake manifold is to remove and replace but the V8 FSI is a significant hassle. 6 hours does seem like an extremely short amount of time but given the widespread problem with the V6s, I wouldn't be surprised if they do in fact have a fairly smooth procedure for it. You could ask how were the valves cleaned (with what method)? If in doubt, you could've also asked for before/after pictures, but if it's pretty routine now, they probably wouldn't take them.

In the end, if she runs, great! The bummer is when this happens out of warranty and you have to pay out of pocket. That will kill the out-of-warranty market for the V6 FSI cars pretty hard.

[dbc112]

I'm not sure how much easier/more accessible the V6 intake manifold is to remove and replace but the V8 FSI is a significant hassle. 6 hours does seem like an extremely short amount of time but given the widespread problem with the V6s, I wouldn't be surprised if they do in fact have a fairly smooth procedure for it. You could ask how were the valves cleaned (with what method)? If in doubt, you could've also asked for before/after pictures, but if it's pretty routine now, they probably wouldn't take them.

In the end, if she runs, great! The bummer is when this happens out of warranty and you have to pay out of pocket. That will kill the out-of-warranty market for the V6 FSI cars pretty hard.

Killed mine for the RS4.. thats for sure.

[Keaton@JHM]

i think i might have another issue to report about carbon buildup in the 3.2 engine...

my step-father drives an a6 3.2 with the fsi engine. his check engine light has been on for a bit and he said the car has been idling really high on cold startups then going back down to the normal level. he took it into the dealership and they scanned it and found some misfiring fault codes. they said they needed to add a fuel additive because it could be carbon buildup and then wait until the next day to do another cold start. they started it today and still had the same codes/misfires. they told him that he's not using good enough gasoline and that's what's causing the buildup.

him and my mom have been running things by me because they know i like to "tinker with my car". when they first told me about the misfiring and the dealership tech saying "carbon buildup" i told them that i had read about some of the new cars having problems with this issue and since the car was still under warranty, the dealership should take care of it.

like i said, the dealership/service tech is saying that we're not using high-quality gasoline. i practically told my mom "wtf do they expect us to do? drive to the east coast for 93 or mix our own race fuel?!" (we live in cali). anyway, my mom is calling the dealership back to see what the final word is. i just wanted to post this to add some more information. i don't know all of the numbers on my step dad's car to add in any worthwhile data but i will when i can. basically, i'm just posting to keep track of this and checkout all of the info out there.