slight misfire/lack of power

[Tuddie]

took an rs6 for a test drive today and it pulled like a train!, then i stopped to look at the car then when i drove it again and gave it some it sorta misfired its hard to describe it but when it kicked down then went to change up to the next gear there was a loss of power, i took it back to the showroom and a salesman went a run and came back and said it was fine, i then went back out again and it was fine then kept doing it and then stopped doing it, any ideas what it could be from my description sorry its a bit vague its just hard to say what it was like, i thought missfire or faulty plug or lead, it didnt do it ofte but once was enuff for me to be wary, has has fsh, low miles and just had huge major service from audi. garage says it will put it on a diagnostic machine to see what the cause is, sorry to be long winded but i thought id ask on here see if it was a common prob, the car may have been sitting a while too if that helps also low on fuel so they put £30 in it but it still did the lack of power thing after that. shame as im really interested and it went well when running properly.

[exman]

what garage are we talking about?

[amanda1]

And what milage???

[Tuddie]

local garage to me and its done 44k and is mint.

[exman]

maybe damp with the weather we've had and sitting over new year.only asked where as i'm looking for one too and dont want to step on anyones toes as i see you are from scotland

[Tuddie]

i got word of it from a friend, its not up for sale yet, there lookng into it tomorrow so i will see what they say, good luck finding one mate there very rare up here.

[exman]

yea dont i know it, have one just up the road from me but not the right colour for me

[ChrisRS6]

It's worth the travel to find the right one! I did around a 250 mile round-trip to pick up mine .... And I'm sure that will be an awful lot less than some had to travel!

[Rupert]

its hard to describe it but when it kicked down then went to change up to the next gear there was a loss of power, i took it back to the showroom and a salesman went a run and came back and said it was fine,

Mine did this years ago. It was intermittent. I think it was a boost control solenoid, a relatively inexpensive fix.
When it changed into 2nd, or 3rd gear it would have no turbo boost, it felt like 300bhp, but it wouldn't do it every time.
When it was in "no boost" mode it would take a while for it to return to normal, with me prodding the throttle in the meantime.
Diagnosed and fixed by Audi dealer and hasn't returned since.

[Digger]

I'm guessing mind but if its the one I think it is which I inquired about a month or two back (mugello, roof, and a milltek?) I think they were looking at top money so may have been sitting unused for a while? Just a guess mind. I would have definitely been to see that one if had been nearer.

[A20LEE]

I wouldn't buy any RS6 unless Unit20 or MRC had given it a health check. When i bought my RS4 three years ago i had it serviced before delivery at awesome gti store as part of the deal. The possiblity of these car stinging you for £5-10k in one year on repairs is very real.

The trader next door to me bought an RS6 from auction last month and the DRC failed after four days and the dealers quoted him £4k to fix it.

[Tuddie]

the garage phoned me today, said it was diagnosed as a faulty coil pack, do you reckon it could be just that? im not so sure but they said i can test drive it for as long as i want before i sign the deal, dunno what to do, ive told them to wait till the coil pack arrives and see how it is. not sure what to do, they have loads of nice cars in like ferraris etc so they should have some knowledge of what they are doing you would think. i told them to not switch off the car before they diagnose the fault so will see if they get back to me with anymore info.

[Shoppinit]

Could be coil pack. Not known for failing on the RS6 particularly. Only you can know if this sounds likely based on your experience of driving it. You should have been able to feel a cylinder not firing.

Even when you buy them and they are working perfectly you still cross your fingers and toes. Buying one with an undiagnosed problem is very brave.

[Tuddie]

it did feel like it was holding back so initially thought coil pack or lead or plug but after reading more on here and srs.com im now in two minds, haha i really dont know what to do, will wait and see what they say when they get back to me, i dont wanna jump in and get stung.

[R1NGA]

I would also get new N75 boost control valve (do a search for full info). About £40 and money well spent. A common failure and I've had 2 in 3 years....

PG