MissouriGirl

I have a 2011 Q7 that now has 120,000 miles on it. About every 50th time that I start it, it turns and turns and turns and never catches. I wait a few mins and it starts. This has happened about 8 times over the last 6 months. Two of those 8 times, however, after I put the car in gear, it slips a few times, going, then not going, going, then not going....and after about 1/4 mile of this, it quits this and everything is fine. . I have brought it to the dealership 3 times, and they cannot find anything wrong. So, I keep driving, praying it doesn't happen again. And it doesn't for a month or so, and then it does it again.

The only things that have gone wrong with this car is that it tends to burn oil just a little and the thermostat went out about 10,000 miles ago.

I know there is something wrong, and it is probably something major. I just don't know what else to do. Does anyone have any ideas, please? Thank you so much!

D3Audi

Do you have a code reader? If not take it to Autozone, they should scan for free, just to see if it is throwing any codes or if it has in the past. Try to video it next time it does it so you can show dealership..

MissouriGirl

Hi. Thanks so much for the suggestion. Audi actually hooked it up 3times and no codes were identified... Any other thoughts? Thanks so much!

davidbod

That sounds like a problem with the ring gear on the flywheel. If the engine stops at a point where the ring gear has damaged teeth relative to the starter motor gear teeth, when you go to start it the next time the starter motor would just spin. The flywheel is also where the engine and transmission mate. That's a transmission pull for sure to fix it. Can't believe the shop you took it to couldn't diagnose that.

smith2010Q7

the 8HP has a system to maintain hydraulic pressure even when the engine isn’t running and is therefore the first automatic that’s compatible with stop-start operation—good for 11 percent better fuel efficiency,

What you are discussing is your trans is losing its Hydraulic pressure and by a 1/4 of a mile the pressure finally has built up to be normal. Sounds like your Transmission hydraulic pump is intermitting. Has not total cause a code in the TCM.

MissouriGirl

Thank you so much for the suggestion! I really appreciate you taking the time to do so. I will be discussing this and the other suggestions with the service center at our Audi dealership here in KC. Thanks again!

Edd W

If you go along with the theory about loosing residual pressure when parked, I would try a fluid change first. It may be lost if these is a more serious issue with the transmission but it would possibly cure the problem.

MissouriGirl

Thanks again to all that have replied. I am heading to mechanic this afternoon. Will keep you all posted. Thanks!

MissouriGirl

Hi all, I wanted to provide an update on what I found out. I took my Q7 to an Audi import specialist yesterday. They did the computer check, and a code was identified related to the master control panel. He said that it is the only thing that might explain what is going on...that there might be a loose wire in the push start ignition area (which I use 99% of the time), which is within the master control area of the car. So he said that he would be curious to see if I ever have this issue when I use the key in the ignition instead of the push start. I don't know the answer to that at this point. I guess I will wait and see.

Another thought he had was that the car not wanting to go once it does start could be due to the car starting in "safe" or "limp" mode, which apparently is a safety mechanism. He said that when it starts in this mode, it starts in 3rd or 4th gear and so once I get a little speed, it operates fine since the speed of the car has caught up with the gear. He said that when it happens next I should look at the dash and see what gears are illuminated. In safe mode, all the gears will be illuminated, not just the "D". If I find this to be the case, then I can assume that there is a random computer glitch that created the limp start issue.

We confirmed that the issue is not the ring gear on the flywheel missing teeth since the car starter is engaging. And when the car doesn't start, the noise it makes is not different from the times when the car does start. Apparently if it were a ring gear issue, I would hear a much different sound.

I don't know if I have made any sense here. I would welcome feedback, if you have any. Thanks again!

smith2010Q7

Everything sounds Correct.