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

This is a very specific problem that I can reproduce everytime. If I am gently trundling along in 6th gear at about 45 mph, if I spy a gap in the traffic and drop to 3rd gear and then go for it - I get a very distinct misfire for about half a second then it clears. It will only do this if I blip the throttle during the downshift to match the revs to the gear. A very basic test it to dip the clutch while your driving along and try to rev the engine. Not only is it quite annoying, but it's bloody dangerous when I'm on the wrong side of the road expecting a good dose of power to complete my overtake, but all I get it big hesitation. I have taken it to my local Audi dealer and the tech can now recreate the issue every time he does it, and he is totally on my side, agreeing that there is a definate hesitation. They have 2 other RS4's at the dealers and they both display the same problem when driven like this. They have changed the clutch switch, just in case the ECU was detecting that the clutch was not engaged, and thus instigating the misfire to save clutch damage. They have reported the problem to Audi Headoffice (whoever they are), and are waiting for a response. Until then, I'm interested to hear if anyone else's RS4 does the same. Remember - it will only do this when you blip the throttle during the downshift.

I look forward to your results.
Simon

Yep mine did this IIRC. It's gone now sadly but I'm sure this is a trait of them all.

What engine ECU software version do you have - 0050, 0080 or 0090?

Mine did this going from 6th into 4th about a week ago. I did this as some traffic lights changed from green to amber in order to pull safely through - one of those split moment decisions, "do I brake or accelarate through"?
It felt like hitting some sort of rev limiter and yet I was nowhere near it. Agree, it was dangerous!
Not sure if it has anything to do with ESP. Try it again with ESP disabled.

Nick

It feels like it is more to do with ESP, doesn't do it when fully disabled.

If it do's this with the traction control off (short press on the ESP button) then it has the same fault as mine started to do.
Coked up valves i'm afraid. Mine ok now new engine fitted.

short press of ESP is only psrtially diabled, 4-5 second press and warning light constantly on is ESP off. On which did you do it Gazzer for your engine to be replaced?

P_G wrote:short press of ESP is only psrtially diabled, 4-5 second press and warning light constantly on is ESP off. On which did you do it Gazzer for your engine to be replaced?

Dont understand your question?

Short press disables the traction control, this i found early on with my car, would stop the hesitation when changing down a gear, didn't need to switch it all off.
But just previous to the new engine, i had hesitation when changing down in a big way, and even with the traction off or esp all off, it still did it.
Audi dealer was told to remove inlet manifold and check manifold flaps amongst other things, this was when they saw the state of my valve coking.
Hope this answers your question.

look at the solenoid valve under the air filter housing. They are prone to cracking... Vaccuum escapes when under harsh loads.