Carbon build up?

[rothschild]

Hi to all, I'm new here, but I've been reading the forum for a long time now. Here is the problem. I'm well aware of carbon build up problem on our cars and as most of you guys was sort of hoping that it won't necessarily apply on me in any way. But I guess it did.

A 2007 Rs4 with Less than 19k miles on the clock. The car still feels alright and not slow but that surge of power after 5500 rpm isn't there anymore. What happens is it just climbs up the revs with probably the same pace as it does before the 5500 rpm mark. No codes or errors, no detonation or pinging. So what do you think guys? Carbon or carbon not? =)

[pippyrips]

more likely vacuum leak or problem with the flaps in either the inlet manifold or airbox.

[klauster]

nope, sounds like it needs a software update, and the vaccum checked for air leaks, faults etc... mine got sorted, and mine was acting very similar to yours

[lengster1]

I would look at the soleniod that opens the flap in the airbox,mine was replaced under warrenty at 26k,if your epc light ever comes on then the vanes in the inlet manifold are probably gunked up,mine had a new manifold at the same time,i put it down to the previous owner not revving it that high that often!!

[P_G]

Same as above, airbox power flap or vacuum leak plus firmware update possibly.

The surge comes from the extraflow of air with airbox flap opening at 5500rpm so if yours does not it's nothing to do with carbonation.

[HYFR]

Carbon

Mines on 70k....it had lost its power kick after 5.5k rpm

had it in Audi for 2 weeks

two sensors replaced linked to the vacum/manifold type area

hey presto, power kick at 5.5k RPM is back and car is fast as f**k

answer = not carbon

[rothschild]

Thanks, guys! Booked an appointment for sunday (going to change my air filter as well). By the way, how updating the software may be of any help?

And returning to carbonation. Are there any other symptoms I should pay attention to?

[P_G]

Carbon

Mines on 70k....it had lost its power kick after 5.5k rpm

had it in Audi for 2 weeks

two sensors replaced linked to the vacum/manifold type area

hey presto, power kick at 5.5k RPM is back and car is fast as f**k

answer = not carbon

David, what were the two sensors that were replaced?

[scaghead]

Thanks, guys! Booked an appointment for sunday (going to change my air filter as well). By the way, how updating the software may be of any help?

And returning to carbonation. Are there any other symptoms I should pay attention to?

sims is your man on this one

[Dom81]

sims is your man on this one

He has an opinion, but (as far as I'm aware) no first hand experience

Closest you get for that is Pippyrips, who had work done to remove and prevent the buildup. He ran the same figures on a dyno (same day) as rAudiguy who'd had similar mods but no decoking, and from what I hear the deposits returned anyway

If Rob's not around, SR71 can advise on the work done to the car

[Sims]

sims is your man on this one

He has an opinion, but (as far as I'm aware) no first hand experience

Correct answer

I have not been affected, but have of course read about many who have.

Also I don't want to be affected, and therefore my ongoing interest.

[rothschild]

Update. Just came back from the service. They couldn't find anything anything wrong with the engine. The only problem was a very very dirty air filter which was obviously changed. And on the way back, I must say the car felt just as fast as hell

[pippyrips]

sims is your man on this one

He has an opinion, but (as far as I'm aware) no first hand experience

Closest you get for that is Pippyrips, who had work done to remove and prevent the buildup. He ran the same figures on a dyno (same day) as rAudiguy who'd had similar mods but no decoking, and from what I hear the deposits returned anyway

If Rob's not around, SR71 can advise on the work done to the car

still here