Hey all,
Relative newbie here; I've used info here before on my a4 avant, but recently purchased a used 2000 A6 avant 2.8 and have some issues with the a6 and looking for some help. The A6 has about 130k miles, so has been around the block a few times. I have not been driving lately due to difficulty in starting, which has gotten much more difficult with the cold weather in upstate NY. When cold starting, starter engages fine and engine trys to turn over, but seems like lack of ignition or fuel to the plugs. After a few minutes of trying to start, engine starts to catch but stalls out. Keep trying to start and it finally holds an idle. If I give it any gas during intial idle, it sputters and then stalls. If it takes the gas when cold and rpm goes above 1000rpm, typically get backfires. After 5 minutes or so, the engine seems to run fine, but still have the same problem starting the following day. There was no CEL when the starting problems started, but the CEL popped up a few days ago. I ran a Vag diagnostic and it showed a misfire on cylinder 3. Cleared the code to see if it would re-appear or if it was a random misfire. Still had the same problems starting the cold engine, but got it started after a few minutes and it didn't trip another CEL. So, I am hoping for a little advice in diagnosing the problem before I have to take to a shop. Any help would be greatly appreciated. Hard starting was the problem before the CEL light came on, but the car has exhibited the same starting/running characteristics with or withouth the CEL on. Seems to run great once started, so I am hoping it is a minor fix.

 

I'd start with the fuel pump. Classic symptoms. After that, there are a lot of electronics, but bad electronics tend to throw some kind of code so I would start with the fuel pump diagnostics.

Bob

 

Thanks for the reply Bob. Sounds like fuel pump could be the issue. I did some research and it looks like it may be accessible, but not an easy replacement. I think I can handle the job, but want to make sure with the diagnosis. What is the best way to determine if the fuel pump is the real issue? I started the car again today; as typical, took about 5 minutes to finally get it going. Ran fine and I drove it for about 15 minutes with no problems. Starts right up easily after it is warmed up, but the CEL did come back on.

Thanks again,
Kevin

 

If you have CEL ON, did you get the code readed? VAG-COM is best tool, but for generic DTC code(s) you can have Autozone do the scan for free (if you are in USA).

 

If you have CEL ON, did you get the code readed? VAG-COM is best tool, but for generic DTC code(s) you can have Autozone / Pepboys do the scan for free (in the USA).

 

You need to check the fuel pressure with a fuel pressure checker.

Bob

 

Any thoughts on whether the hard cold starting problem could be the engine coolant temperature sensor? I just ran a scan with Vag-com and came up with the P0117 - Engine Coolant Temp Sensor - Signal too low. Can the ECT sensor lead to the hard cold starting? Looks like a cheap and relatively easy fix, so I am hoping that this is the problem.

Kevin

 

Possible. Certainly a cheap item that is known to go bad so it is a good first shot.

 

Just finished replacing the ECT sensor and the car started right up after installation, so apparently this was the problem. Kind of a pain in the **** job for a cheap part and someone with big hands, but thanks to advice found in this forum, I was able to get it done. Now that it is starting in the cold, I'll have to move onto some of the other problems. Car was in a front end accident before I purchased and not correctly repaired. There is a leak in the windshield washer reservoir, the AC auxilliary fan stays on too long after the car has stopped event in this cold weather, and I am not sure if the oil pressure gage is working.

 

The windshield washer tanks and/or lines always leak. If you have headlamp washers, start there as that seems to be a lot of peoples problem area.

Oil "pressure" gauge? Do you mean oil temperature gauge? Since it is measuring temperature, it will be a bit sluggish in this weather.

Bob