I have a 2006 A6 with just shy of 40,000 miles. When I first got the car at about 24,000 miles it had normal, cold start cranking times. By cold start, I am meaning after full cooldown, even now in May, sitting overnight. It can take 4 seconds plus of cranking to start, and I have had it take longer.

The long story short brings me to this summary:
The dealer, after having had the car a third time, says they phoned Audi and were told this fuel injection system can take 3-5 seconds cranking time when cold. I point out that my 2006 A4 and their 2009 A4 loaner car start very quickly when cold. After some mumbling in the background they offer up the notion that the A4 is a different system and that explains that difference.

1. What are you seeing for cold crank times (measured in seconds) to start on your 3.2 A6?

2. Does the A6 actually have a different FI system than the A4?

A man I know who runs an import garage listened to it and without me saying anything, told me it cranked too long. He went on to say it should be diagnosed by making pressure checks with a mechanical gauge. He said he could do that, but since this car is on warranty, Audi should do that, not me.

I raise that with the dealer and they say their pressures come from a computer scan. That scan relies on electronic sensors in the FI system to provide the numbers. Obviously if they are bad, the numbers will not be accurate.

The dealer says they can't do system pressure tests on the high side of the system because the developed pressures make that too dangerous. The import garage guy says otherwise. Thoughts on this? Any experiences in getting a car diagnosed that can provide me some direction here?

Discuss.

 

i Have cold start issues as well...dealer proformed some TSB's but still having. Now with the summer months the problem has gone away though. Try pumping the gas twice and turning and leaving the key in the aux position for a second then crank. that helps.

 

There are several TSBs regarding cold start problems. Drop me a PM with your e-mail address and refernce the cold start problem. I will e-mail you the TSBs.

 

I would not think pumping the pedal would have any effect, given that it is fuel injection.

 

Kevin, I believe you, very kindly, sent me four once before. Sadly, they did not seem to yield a solution.

My frustration is that they refuse to do anything other than a scan. That forces them to assume all sensors are accurate. A bad assumption.

 

can you hear your fuel pump whining.

Have you changed your fuel filter lately?

That sounds like a fuel issue. As stated leave the key in on before cranking as if it had glow plugs if that resloves your issue than either your fuel filter is clogged or your fuel pump is going, pressure regulator could be leaking.
Also somebody said there was something wrong with the airflap not opening fast enough. I'm not sure how you wuold test that.

Don't pump it. That tells the ECM other things.

 

Yes.

No. Good point. An observation, however. It runs and accelerates and will go 80 mph plus with ease. That suggests it has good fuel flow. Not to say I should not replace the filter, however.

Cycling the key several times seems to help, though not resolve, the issue.

What is the air flap?

 

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Thats not the way fuel pumps quit really. usaully they get bad when they are hot, then quit then work when they cool down. but you also need to re-pressurize the system in the morning. If the filter is restricting flow it may not be comming to pressure fast enough. I had this problem on a truck the filter was packed and it only had 18K on the dial.
It was hard starting but once it pressurized it was fine and it was getting 6MPG at best so it used alot of fuel, but only gave a problem in the morning. Worth a try. It is deffinatley where I would start checking. 5 min to replace it. you can bang it out and see all of the dirt.

Look on the threads about the flap I just heard about it. I have misfire dilemas myself. Theres a post on now about one

 

There is a TSB on the fuel filter as well. Let me know.