RS246.com Forum :: The World's #1 Audi R, S and RS Enthusiast Community

Any help from knowlegeable S4 gurus would be most welcome.
This is a very long story but basically I have an RS4 engine in a 1998 S4 running on the S4 wiring and ECU. I would have had to rewire the whole car to get it running on the RS4 ECU. EVERYTHING else is RS4 - complete intake, injectors, airbox, fuel pump, intercoolers etc etc. I had a map put on the ECU by a very well known chap who has done this spec. before on another vehicle where it made 475bhp. That would do nicely, except that we cannot get it to maintain boost pressure. We can fool it by clamping a pipe so we know the turbo's are good and there are no air leaks. There are no fault codes. We have changed the MAF, the MAP sensor, boost solenoid etc but to no avail. The only thing I can see that has not been changed is the ECU itself. Does anybody have any thoughts on this problem? Does anybody have a C type ECU lying around that I could try? [img]images/graemlins/confused.gif[/img]

Speak to AmD, they are knowledgeable enough to help

Nice project BTW

There was a C S4 ECU on ebay a while back but I can't find any details now.

I'll keep looking though [img]images/graemlins/thumbs.gif[/img]

Hi Giles - glad you got yourself behind the wheel of what looks like a "well sorted" S4. Pics look good too.

Did you know that you can pick up a new ECU from VAG parts for about £200 or so - I would expect the the "C" type would be the one as the "D" prefix applies to the pre-facelift models.

Who is doing your tuning by the way?

What pictures?

Hi Giles - glad you got yourself behind the wheel of what looks like a "well sorted" S4. Pics look good too.

Did you know that you can pick up a new ECU from VAG parts for about £200 or so - I would expect the the "C" type would be the one as the "D" prefix applies to the pre-facelift models.

Who is doing your tuning by the way?

I thought the D prefix one applied to post-facelift models! [img]images/graemlins/confused.gif[/img]

What pictures?

In the Gallery mate [img]images/graemlins/grin.gif[/img]

I thought the D prefix one applied to post-facelift models! [img]images/graemlins/confused.gif[/img]

I can't find the photo of my pre facelift ECU with the prefix - just thought that it was a D but I may have been mistaken? [img]images/graemlins/confused.gif[/img]

Mine's a post facelift car with a D ECU.

S4RS4, you have a PM.

DavidT wrote:S4RS4, you have a PM.

I found a 'C' ECU from a guy on ebay and PM'd you the details just before the site changeover.

Did you manage to resolve the problems you were having ?

This sounds a bit like my current problem....also have a 1998 S4 with KO4's and cant get it to maintain boost and as a result its producing power on the low side...both bhp and torque. Tuner say they have tried everything. Am waiting for MTM to come over to have a look...Would be very interested in your findings if you locate the problem. Not sure about my ECU type though...

Mik

have you guys tried MBCs! pressure regulator should set the max and relief valve how hard it comes. s4 with k04s and stg1 chip benefit of relief valve in paraller with n75-valve to keep the boost spikes and possibly throttle cut away!