I have searched the forum for the same problem my 04 2.7t is doing.... no direction tosolve the problem........????

I have an automatic s line and some times(not all the time,more often whem stopped and turning a corner)when I start from a stop and start up with normal gas pedal accelleration the care feels like the turbo has turned off 1st through 3rd gear (it also rpms high through each gear)
I have to push the pedal down more than normal to get it going, then it really takes off. I know this is not normal. I have vagcom and have checked for codes and did the TBA adjustments.I changed the spark plugs,put a new K&N filter and had the TBelt service done.(currently 76000 miles)

Could it be a bad sensor,leaky vacum hose,someting to do with thetransmission,do I need a new fuel filter (I use the high octane fuel), could it be a clogged cat, or dirty throttle body??????

I know if I take it to the shop,they will hook it up to vagcom and find nothing like I did. Is there somewhere in vagcom I am overlooking to see if I can identify the problem source?

This has been very frustrating [:@]to me as I just bought this car and has seemed like all it likes is money!!! I hope it is nothing major or is thisjust how these care run!!!

If you can tell me where to start to eliminate the problem.... Please help if you can. Thanks!!!

 

Well since you have a vag com lets look at some data blocks.
Find your throttle angle percentage, this shouldn't be over 2.5% when the engine is running. I think its somewhere between 1 and 5 in the engine electronics.
Check the coolant temp when the engine is running, rev the engine and check to see if the coolant temp does anything crazy like go to -40 degrees for a split second or something like that.
Look at the Mass airflow sensor data, it should register in g/s. It shouldn't be higher than 6.0 at idle, also make sure it stays steady.
Then go to data block 32 which is the fuel trim, make sure its close to 0%, if its higher than 1% + or - post what it is.
Lastly find the O2 sensors and see what those are, to make sure there isn't a vaccum leak.

 

Thanks for you expertise and asking questions to help,I realy appriciate it very much. I highlighted in redanswers below to make this as simple as possible.There are so many different codes to look for anddo you thinkit wouldbe a good idea to get a shop manual to know what to look for? There is definitely something going wrong in this car,and I hope it is simple and nothing major such as transmission,tork converter or turbo issue...that would be a big bummer!![:@]

Well since you have a vag com lets look at some data blocks.
Find your throttle angle percentage, this shouldn't be over 2.5% when the engine is running. I think its somewhere between 1 and 5 in the engine electronics.
003-@650rpm throttle angle shows 2.4 to 2.7% it jumps aroundvery fast. mass air in this block is 358g/s

Check the coolant temp when the engine is running, rev the engine and check to see if the coolant temp does anything crazy like go to -40 degrees for a split second or something like that.
001 -engine temp is constant warmed up to 96 and stayed throttle or not

Look at the Mass airflow sensor data, it should register in g/s. It shouldn't be higher than 6.0 at idle, also make sure it stays steady.
002 - load measurement @650 rpm mass air 3.47 -4.00g/s Jumps inbetween numbers very fast

Then go to data block 32 which is the fuel trim, make sure its close to 0%, if its higher than 1% + or - post what it is.
032 - ??I tried tofind fuel trimin 032 but must be another number? I looked in engine measure blocks,is it somewhere else?

Lastly find the O2 sensors and see what those are, to make sure there isn't a vaccum leak.
002 - 02 bank 1 @680rpm idle 0.8 to 3.9 @1500rpm0 to -3.3 the numbers change very fast back an forth
02 bank 2@650rpm idle -3.9 to 1.6 @1500rpm 0 to -3.1the numbers change very fast back and forth

Again,thanks for your imput and helping with my frustration.

 

Everything looks ok except for the mass air flow at 358g/s in the data block 003, are you sure it didn't read 3.5g/s?
I would try taking out the mass air flow sensor and cleaning it with some electrical contact cleaner that you can get at any auto parts store.

Check your air filter too, if its really dirty change it.
As for the repair manual, no manual will tell you what the data blocks are. Hell, on the factory tool it doesn't even tell us what were looking at! The VAG COM is better than the factory tool, at least it tells you what your looking at!

 

sorry It did show 3.58 in 003

It also showed 3.47 -4.00 in 002 jumping around quite quickly.

where else could I look for the fuel trim? I tried 032

I put a new K&n filter in the car when I changed the plugs I will clean the air mass sensor to see if that helps.

What about a new fuel filter and a good cleaner to run in the gas to help clean the injectors??

Thanks

This car sucks the gas...Irange from 13-15 in town even when I drive like granny

 

Ahhh, the K&N filter may the problem. K&N filters use oil which is known to foul up the mass air flow sensors. I use a K&N filter too, but i washed it so the oil isn't present. Try cleaning the mass air flow sensor, it should fix the problem if no fault codes are present.

As for data block 32, it should be fuel trim. You might wanna re-check it, but as far as the O2 sensors are reading, it really doesn't matter.

 

I never thought about that.....I will go buy a cheap air filter to use while I clean the K&n and then clean the sensor

What are your thoughts for a new fuel filter and a good injector cleaner???

Thanks for your advise!!

 

Fuel filters are a good PM maintance at around 80k, but they usually don't cause problems.
Fuel injector cleaners really aren't needed if you use good fuels, but if you want to do it anyway, the dealer has the best fuel system cleaners such as BG. If you just wanna get them cleaned up a little bit pour a can of seafoam into the gas tank which you can get at any auto parts store.

 

Thanks!!
I forgot about the seafoam.I have used it before and had good results in a different rig.
The car is at about 77000 and I might as well change the fuel filter.I need to chane my gas fill uptocheveron instead of Flying J. I always use the highest octane and should know better to get it at a cheveron as I used to own a Subaru turbo 2.2.

Thanks for all your help!!!

 

Great info by Auditech79 as usual...

As for Seafoam and Fuel filter, I would do the seafoam first, then change the filter after you go through a tank of gas. Fuel filter is located on the right side of the car right in front of the rear wheel well. You need 17 mm, 19 mm and an adjustable crescent wrench to replace the filter. Also be sure to get 4 aluminum sealing washers to replace the existing. Becareful, because 2 inlet washers are larger than the 2 outlet washers. I had an issue with ordering 4 washers from internet thinking that they would get it right, but all 4 were the same. I had to go to a local hardware store to get different ones.

As for replacing the filter, pull your fuel pump fuse. Start the car and let it just die. Open the fuel door to release pressure in the gas tank, then loosen the fuel hoses. You will see a lot of fuel spilling out of the line, but it is ok. Also don't forget M10 triple square bit for the strap that holds the fuel filter.

Once the fuel filter is installed, reinstall the fuse for the fuel pump. Check and make sure your gas cap is closed, and restart the car. It will take a few cranks to start. Once started turn it off and recheck the fuel hose connections to the filter. Make sure it is not leaking.

After seafoam, fuel filter and routine maintenance stuff, my car runs a lot better now. It is definitely noticible.