A80 2.8q

[phil2.016v]

Hi Fellas,

Just thought i'd pick some brains!!

My Bro has just bought an A80 2.8 q sport in great nick. The problem is it feels flat at the top end. I had one years ago and can't remember if that's the way they are or if it's got a problem. Are there any obvious or common probs with these V6's??

[tris70uk]

I had an 80 2.8 quattro and never thought it flat at top end, he hasn't gone from a turbo car has he??

I can't remember the exact revs but there is a set of buterflies in the inlet manifold that change over the routing of the air to the heads, to give better power at both top end and bottom end.
This is powered by vacuum, there is a small vacuum resevoir close to the coils (under the engine top cover at the front of the engine). I would recomend checking all the pipework for this set up. If you have vagcom you should be able to test the solenoid valve that controls it all.

Somewhere to start at least.

Jon

[jdcorr]

Check/replace the lamda probes (One on each downpipe). Made a big difference on my brothers 80q.

[phil2.016v]

Cheers fellas, a good start! He's come from a Vento VR6 which obviously behaves more like a twin cam than the wide v audi lump, but I've been using it this week and it does feel restricted after 4k.

[kninio]

look like the change over dual intake manifold is not working

[amanda]

hmmmm mines a v6 but not the 8o one and if anything mines sluggish under 3500 revs anything over and shes fine

[Cullam3n]

Make sure you don't have any vacuum leaks, particular the one that is connected to the throttle body housing. Also like someone said check the vacuum canister that sits under the coil pack on the left side. If you can pull the vacuum line out after running the car you should hear like a gasp of air coming out; if you don't check your lines

Shouldn't feel flat, should be a noticeable increase in the sound and kick (not quite turbo ). Only the 2.6 v6 should feel flat in the top.

[fzr phil]

Hi,
Also, i find my 2.8 can be sensitive to fuel. esp on 95, even on 97. either tesco 99 or v-power might bring the top end back to life. assume basics like air/fuel filter and sp plugs are ok?
i rolling road tested mine the other month on 95 fuel, had also been feeling flat over 4k.
the data showed this!
switched fuels back to 99 and have found the car more willing to pull and rev, though i also at times have not been convinced the manifold butterfly switched over.
the other thing is because of the adaptive ecu, i think the cars can go into lazy mode.
the vr6 is at least over 20bhp more and lighter as well. expect the v6 quattro would feel a bit lardy!

hope that helps

Phil

[phil2.016v]

I've checked all of the Vacuum lines and they all look new, the car does change tone over 4k as it seems to go quite as if something is going to happen....but it doesn't!!

I'll get it plugged into Vagcom and see if I have any faults.

Phil, the vento is 174 bhp so about the same power. I'll try some 99 fuel, but I think there is a problem somewhere.

I know these cars aren't ballistic as I've had an S2 before, but they should pull to the redline, this one really struggles to get over 5k!!!

[Cullam3n]

Sounds like it may be a clogged fuel filter? Not getting enough fuel at those rpms? Just throwing out an idea. Doubt it's because of 95, I use 95 half the time and it pulls fine.