Out of ideas..2001 A6 2.8Q
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Junior Member
Joined: Jan 2010
Posts: 20
Out of ideas..2001 A6 2.8Q
I posted this a few days ago and did the suggested repair of replacing the coolant temp sensor. This made the CEL disappear and I saw about a 3 mpg jump in fuel economy. However, my starting problem when the car is warm is still present.
When I start the car in the morning it starts up perfectly fine. One turn-over and it is good to go. When I shut the car off, as long as I start it within about 5 minutes it starts up right away. However, after anywhere from 10 minutes to 4 hours later it will take 6-8 seconds to start. During this time when it starts up the rpm's will idle at 200 for a second seemingly teetering on the edge of shutting off (which it will do on occasion), then jump up to 400 for a second, then to 600 for a second before permenately idling around 800. This indicated to me that there was a fuel problem, likely pressure related.
Here are the repairs I have done thus far - mostly time change items (totaling $1,400):
August - Fuel Pump & Fuel Filter
September - Coil Pack (all 6)
November - Timing Belt, Serp Belt, Water Pump & Spark Plugs
December - Battery & Vaccum Hoses
January - Fuel Pressure Regulator (prior to replacing this it could take as long as 15 seconds to start). Coolant Temp Sensor
Any ideas on where to go from here? Also does anyone have a link to directions to replace the driver side mirror?
When I start the car in the morning it starts up perfectly fine. One turn-over and it is good to go. When I shut the car off, as long as I start it within about 5 minutes it starts up right away. However, after anywhere from 10 minutes to 4 hours later it will take 6-8 seconds to start. During this time when it starts up the rpm's will idle at 200 for a second seemingly teetering on the edge of shutting off (which it will do on occasion), then jump up to 400 for a second, then to 600 for a second before permenately idling around 800. This indicated to me that there was a fuel problem, likely pressure related.
Here are the repairs I have done thus far - mostly time change items (totaling $1,400):
August - Fuel Pump & Fuel Filter
September - Coil Pack (all 6)
November - Timing Belt, Serp Belt, Water Pump & Spark Plugs
December - Battery & Vaccum Hoses
January - Fuel Pressure Regulator (prior to replacing this it could take as long as 15 seconds to start). Coolant Temp Sensor
Any ideas on where to go from here? Also does anyone have a link to directions to replace the driver side mirror?
3rd Gear
Joined: Nov 2007
Posts: 1,980
From: Northern California
You need a vandal proof torx bit, which is a torx bit with a hole in the middle.
1. Remove the beauty cover above the air box.
2. Disconnect the wiring to the MAF sensor.
3. Unscrew 2 vandal proof torx bit.
4. Pull out the sensor and clean with MAF sensor spray that you can buy from any auto parts houses.
1. Remove the beauty cover above the air box.
2. Disconnect the wiring to the MAF sensor.
3. Unscrew 2 vandal proof torx bit.
4. Pull out the sensor and clean with MAF sensor spray that you can buy from any auto parts houses.
3rd Gear
Joined: Dec 2008
Posts: 1,941
From: IL
The crappy start it also may point to a faulty Ignition Control Module or on its way out, while for the idling problems the Idle Control Valve (unit) may be the culprit.
If you chased the same problem for so many months and spending all those money in ignition, fuel and vacuum related parts, then you may ought to look into ICM and ICV too.
If you chased the same problem for so many months and spending all those money in ignition, fuel and vacuum related parts, then you may ought to look into ICM and ICV too.
3rd Gear
Joined: Nov 2007
Posts: 1,980
From: Northern California
ATQ does not have ICV. And the symptom does not sound like electrical issue, but rather a fuel/air issue, so I am not sure whether the ICM is bad...
Another thing to check is to clean the throttle body and run through a throttle body calibration. Just shoot the MAF cleaner spray once you disconnect the flexible intake run between the air box and the throttle body. Make sure to shoot some at the air temperature sensor too. Then try to start the car. It will run crap, if not run for several crank. Once starts, you may actually get some new CEL, too. No worries...
Anyways, after that, disconnect the battery, reconnect it, and turn the ignition to on position without starting the car. It will go through the throttle body calibration. You will also hear a faint motor sound from the throttle body. Wait about 3 minutes or wait for the sound to go away. Then you are done.
Do you have VAGcom?
Another thing to check is to clean the throttle body and run through a throttle body calibration. Just shoot the MAF cleaner spray once you disconnect the flexible intake run between the air box and the throttle body. Make sure to shoot some at the air temperature sensor too. Then try to start the car. It will run crap, if not run for several crank. Once starts, you may actually get some new CEL, too. No worries...
Anyways, after that, disconnect the battery, reconnect it, and turn the ignition to on position without starting the car. It will go through the throttle body calibration. You will also hear a faint motor sound from the throttle body. Wait about 3 minutes or wait for the sound to go away. Then you are done.
Do you have VAGcom?
3rd Gear
Joined: Sep 2004
Posts: 2,371
From: Newfields NH
Auditech79 sugested doing a motor clean for hard starting. He said that carbon buildup can be the culprit.
I called Merry Maids and asked them if they could do a deep cleaning of my Audi and after a pause the line went dead. Then I called a guy that claimed to clean and detail vehicles. He just laughed when I said I wanted the interior of my motor cleaned.
Next I got a pail, a few rags, simple green, and a scrub brush. When I got to the car I couldn't find a way to open the motor so I washed the dog instead. You should have heard him howel when I tried to wash his privates with the brush.
Then I remembed that Auditech79 said to use some type of internal motor cleaner so I did a search on his posts and there it was. I will let you have the fun of finding doing your own search for his post cause the dog has disappeared and I've got to find him before the kids show up for the weekend.
I called Merry Maids and asked them if they could do a deep cleaning of my Audi and after a pause the line went dead. Then I called a guy that claimed to clean and detail vehicles. He just laughed when I said I wanted the interior of my motor cleaned.
Next I got a pail, a few rags, simple green, and a scrub brush. When I got to the car I couldn't find a way to open the motor so I washed the dog instead. You should have heard him howel when I tried to wash his privates with the brush.
Then I remembed that Auditech79 said to use some type of internal motor cleaner so I did a search on his posts and there it was. I will let you have the fun of finding doing your own search for his post cause the dog has disappeared and I've got to find him before the kids show up for the weekend.
3rd Gear
Joined: Nov 2007
Posts: 1,980
From: Northern California
Auditech79 sugested doing a motor clean for hard starting. He said that carbon buildup can be the culprit.
I called Merry Maids and asked them if they could do a deep cleaning of my Audi and after a pause the line went dead. Then I called a guy that claimed to clean and detail vehicles. He just laughed when I said I wanted the interior of my motor cleaned.
Next I got a pail, a few rags, simple green, and a scrub brush. When I got to the car I couldn't find a way to open the motor so I washed the dog instead. You should have heard him howel when I tried to wash his privates with the brush.
Then I remembed that Auditech79 said to use some type of internal motor cleaner so I did a search on his posts and there it was. I will let you have the fun of finding doing your own search for his post cause the dog has disappeared and I've got to find him before the kids show up for the weekend.
I called Merry Maids and asked them if they could do a deep cleaning of my Audi and after a pause the line went dead. Then I called a guy that claimed to clean and detail vehicles. He just laughed when I said I wanted the interior of my motor cleaned.
Next I got a pail, a few rags, simple green, and a scrub brush. When I got to the car I couldn't find a way to open the motor so I washed the dog instead. You should have heard him howel when I tried to wash his privates with the brush.
Then I remembed that Auditech79 said to use some type of internal motor cleaner so I did a search on his posts and there it was. I will let you have the fun of finding doing your own search for his post cause the dog has disappeared and I've got to find him before the kids show up for the weekend.
