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The mrs is away so just popped out for a quick thrash ( in the car not the bathroom) and for the second time recently I had a really uneven throttle response. Really slow and steady - fine. Flat to the floor - fine. Came to a roundabout at an acceptable speed, started squeezing on the power in the exit and really lumpy response, almost stuttering also the ESP/traction light came on? I was passed the corner by this point and no where near loosing grip.
Any ideas?
No warning lights at mo but don't have a vag.com as it scares me..

marv8 wrote:The mrs is away so just popped out for a quick thrash ( in the car not the bathroom) and for the second time recently I had a really uneven throttle response. Really slow and steady - fine. Flat to the floor - fine. Came to a roundabout at an acceptable speed, started squeezing on the power in the exit and really lumpy response, almost stuttering also the ESP/traction light came on? I was passed the corner by this point and no where near loosing grip.
Any ideas?
No warning lights at mo but don't have a vag.com as it scares me..

Could it be maf related? Ben??? come on man, a brother is in need

Yeah, I'd say MAF. It could more or less work in closed loop mode, but when you put your foot to the floor and the ECU goes into open loop mode, it really needs those MAF values.

Could be N75, but that doesn't explain the ESP light which the MAF would.

Hmmm had the maf's replaced last year and only covered a few thousand miles. When I originally got the car back from the garage it was driving like crap - easily diagnosed as air box fitted wrongly. Been driving ok since but guess this could have damaged the seals?
She does live outside at the mo not sure that should make a diff though?

Guess I need to go and grab a VCDS - I did have the Secondary air pump code throw up a while back. Wiped it and tested it a few hundred miles later and still clear - guess they are all fuel trim related right?

The real reason I have not got VCDS/vag.com is I have been putting off updating my laptop for the past 5 years or so (technophobe). It is about an 8 year old Sony vaio that only works when plugged in.....
Maybe if I get a decent bonus next month I will go for it - would rather spend the money on the car though!

Could easily be an air leak. When I say MAFs, obviously I meant anything that could give incorrect air flow readings. Seals, air leaks.

Get under the bonnet and start checking the miriad of little vacuum hoses.

Oh, and order a Vagcom, while you're at it

by Shoppinit » 28 Jan, 2012 - 10:08

Oh, and order a vagcom, while you're at it

yeah they should be delivered when you buy an RS6...

r u sure it wasnt the traction control , has it happened when your traction lights arent on ?

it might be the abs sensor, they are located in the hub/axle, they are magnetic and do pick up rust from time to time. This will throw an ESP light and cut power. If you had a VAG it could be easily determined. If you rather check, remove wheels, check behind hub, right on axle there is a bolt(not sure of mm size), but there is a wire that leads to it and disappears into the body. Remove bolt and pull the ABS sensor, clean with brake cleaner and re install. Also check the wiring between bolt and body, they tend to crack over time.

Thanks again gents, will run it down to the garage tomorrow and run a scan.
Phil def not loss of traction, was in 2nd going 40ish in a straight line, don't have the moochers power just yet as standard apart from exhaust.
Will feedback tomorrow most likely with a big list of dtc's

Right slight delay - sorry.

Ran the scan and only 3 fault codes (even the gearbox) phew!

P1423 & P1411 SAI banks 1 & 2 insufficient flow

P0430 cat system bank 2 efficiency below threshold

Are they related and do you think they would cause the hesitant throttle under mid load issue?

CheeRS

I think it's unrelated. Are they intermittent? Normally the SAI would bring up the MIL. What are you reading the codes with?

I take it back. I think it is related.

I'm thinking you have a vacuum leak in the SAI system - possibly the mechanical combination valves - which is screwing up your mixture. You need to log your mixture while driving and at idle.

Thanks Shop,

Will grab the garages laptop tomorrow and run some logs. Would this be under the advanced measurements blocks?

Only just managed to overtake an Astra vxr when the incident happened - that would have been wrong!

Dunno, you didn't say what you are reading the codes with.