Holding Speed

[Seech]

New owner of a B7 RS4 here... I've had an itch to buy one since I first heard it in Le Mans on launch...

Anyway. Trying to iron out a few issues on the car. One thing I notice, albeit subtle, is that when you hold speed at say 70mph, it's like the accelerator is cycling on and off every second or so. It does it on cruise too. My foot will be steady on the pedal but it feels like I'm being a little jerky with it, continuously.

It's not hugely noticeable but wondered if I should be trying the throttle body reset on the FAQs? Will this affect the map? (it's got a stage 2 MRC, Gruppe M induction kit, Miltek). It's had new injectors not that long ago. I'm struggling to even find the right terms to search with!

Aside from that, not sure what else it could be indicative of. H/L pressure fuel pumps on their way out?

Advice appreciated.

Thanks

[highrise]

Hi,

I'm 99% sure resetting the throttle won't impact the map (others can confirm).

More info here: viewtopic.php?t=124222

If you've got access to VCDS or and OBD2 scanner you could look at the live throttle or other data whilst driving. It might be obvious when you graph it to see what's going on. The throttle is electronic so could be a signal issue?

[JRC1]

Are you sure that's not just the MRC map? I also have a Stage 2 mapped car and MRC make the throttle response in S mode incredibly sensitive.
I guess a question is, does it do the same thing when not in Sport mode? If it does then ignore my theory.

Welcome to the forum. What colour/spec did you go for?

[r8wut]

If not cleaned previously, you can give the Throttle Body / Plate a good cleaning (both sides) and try cleaning (very carefully) the MAF with MAF spray.
Then perform a TBA

Ideally, as mentioned you need access to LOG live vehicle data with VCDS - so you can monitor Fuel Trim values and MAF data to see what's going on

Here's a good write-up on it:

http://wiki.ross-tech.com/wiki/index.php/Fuel_Trim_Info

I'm doing something similar with the Wife's RS4 ..