audi s4

[pauls]

Decided i couldnt be bothered for more car hassle. Had enough this year with the omega.

[Marks DTM Calib]

If you do go down this route, drive it hard on a test drive, I have seen to many AWD VAG units with goosed Haldex modules as the owners don't keep the tyre tread depth fairly closely matched.

Of course being an A4 all the suspension bushes will be shot but there are some good heavy duty bush kits about now

[TheBoy]

but there are some good heavy duty bush kits about now

Which still don't seem to last as long as genuine VAG ones, but VAG ones are stupidly expensive (when you consider invariably all 8 pieces need changing pretty much at the same time)

[Viral_Jim]

It does indeed look very nice and will go like stink, depends how much you want the car and how much to fix the rough engine.

As they say, you pays your money and you takes your chance.

It's an Audi. So either it needs a £30 ignition coil(and the garage will have tried that), or something oppsing expensive is wrong with it.

Amongst many other issues, my dad's rs6 had these symptoms. Same engine, rs6 just adds twin blowers. Turned out it was a gear selector issue, meaning the gearbox ecu and engine ecu couldn't sing from the same hymn sheet. Induced rough running, not always present. If I had to guess, the treatment is likely to involve open wallet surgery.

Personally I wouldn't touch it with someone else's  . Unless you feel there's more money's worth of bits in it.

[johnnydog]

[I seem to remember that the 4.2 suffers from carbon build up and needs to be de-coked.


[/quote]

I understand it was the 4.2 engine fitted to the RS4, not the S4 that was prone to carbon fouling. The RS4's fuel was injected directly into to the cylinders, whereas the S4 was injected via the more conventional inlet side, therefore 'washing' out the inlet side before the fuel entered each cylinder. The RS4 suffered from the carbon build up because the fuel didn't 'wash' the inlet side as it was injected directly into each cylinder. Both had a 4.2 V8; the S4 was 344 bhp, whereas the RS4 was 414 bhp, although the effects of carbon fouling greatly reduced this figure in the RS4 overtime.
I had an 4.2 S4 many years ago; lovely engine, good performance, reasonable economy for an engine of that size, but above all, that beautiful V8 burble......