S6 WOT fault

[Knight Rider S4]

I am looking at a friends UrS6 for him to see if I can sort this wierd issue out

Current faults:
The car has a lumpy tick over 760/800 up and down abit

When accelerating WOT it feels retarded in some way and judders at 3500 /4000rpm

Boost gauge is showing 2.0bar(so 1 bar all in )


Things I have done to try a fix problem

Scanned with VAG.com no codes, did full output test and all it working as it should
Checked VAC lines going to ECU and moisture trap all good (1008Mb)
Swapped over MAF no change
Swapped over POS's no change
Checked Coils and they look like they have been changed not long ago ..look new as is the wiring...boots are tired looking and have been wrapped with insulting tape (possible cause)
Did visual check of boost hoses and check clamps to make sure they are tight

The car has been in a garage before it came to me so double checking every they have done ..fitted new speed sensor


So anymore ideas to add to the mix were I should look or test ..plug boots is a high contender ....Would like to test the coils just to make sure one is not fail under load ,The car has this issue with idling as well which makes me think it is something else ..like it is drawing in unmetered air


Cheers


Steve

[UrS4boy]

I am guessing that there is an air leak somewhere or the O2 sensor needs replacement to solve the idling problem. For the WOT missing, that is usually coils but you should start by checking/replacing the spark plugs and the coil to plug boots. If you haven't already done so, have a read through this (and its internal hyperlinks):

http://forums.quattroworld.com/s4s6/msgs/22611.phtml

[UrS4boy]

There are also a few more things that you could investigate in this ENGINE BAY DEVICE MAP.

[Knight Rider S4]

Cheers Dave ...forgot to mention plugs have been changed so has the fuel filter ..will scan through link and see if it brings up anything I have missed

[HMS-S6]

I feel for you, sounds you and i have a very similar problem!!!!