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Hi RS4 owners.

Does anyone know of any common problems with RS4's. other than bent rims.

Just trying to decide whether to go for another S4 and mod it, but a bit concerned about risks with the K03's, or go for an RS4 , [img]images/graemlins/audiS4black.gif[/img]

No major issues, just a few minor ones which have been discussed here. Check the car visually, drive it, then check it visually again, and go from there. Give us some feedback and we will se what we can do. Take a note of the mileage.

Hi!
In my opinion the RS4 has a big problem.
IT´S IRREPLACEABLE!!!
UUUUUUUUUUUOOOOOOOOOOOOOOOOOOSSSSSSSSSSSSSSSSSHHHHHHHHIIIII
YELLOW IMOLA FOURCE
[img]images/graemlins/grrr.gif[/img]

The only real problem with the Rs4 is the amount of money you spend on mods [img]images/graemlins/jump3.gif[/img] [img]images/graemlins/jump3.gif[/img]

i was planning on an s4 avant after selling my rs2 as the rs2 is a bit heavy for everyday driving and this would be my only car.after also reading about all the s4 problems i have decided to spend the extra and go for the rs4 subject to driving and liking it(i cant see this putting me off).
should i stear clear of track day used or modified cars,as i found my rs2 fast enough and very reliable at 130,000 miles. are the standard rs4's in the same leage? [img]images/graemlins/24430-audibash.gif[/img]

Now done 50k in mine and modded from 12k, no problems only failed MAF and synchromesh going on 2nd gear I have heard of a few with gearbox probs but all repaired under warranty

So I would say no probs with either stabdard or modded IMHO

The standard suspension is awefull though and definitely needs upgrading

excuse me for being stupid,i have seen it mentioned but whats the maf.
is warranty 3 years,and up to what mileage.
i dont care about suspention just want the car asap.

MAF = Mass Airflow Sensor.

So I would say no probs with either stabdard or modded IMHO

Don't forget about the soft RS4 alloys - newbies might not know about these - if I was buying an RS4 from a dealer, I would make sure they would agree to replace these as necessary before I signed on the dotted line. [img]images/graemlins/thumbs.gif[/img]

Edit - Ooops - that'll teach me not to read Simons first post !

Not so much a problem, but bear in mind also that whilst the RS4 is far more powerful than an S4, it tends to work higher up the rev range and so at low engine speeds a standard RS4 may seem sluggish compared to the S4 that you are used to. (I know this is what originally got Bushy into modding his, and he too came from an S4)

Like I said, not a problem, but if you want the S4 kick in the ass type feeling that you've no doubt become acustomed to, then be prepared to shell out some Nelsons on the mods! [img]images/graemlins/grin.gif[/img]

Nelsons

[img]images/graemlins/confused.gif[/img]
I thought that you went to a bar for a pint of Nelson [img]images/graemlins/grin.gif[/img]

my partner had a sensor in his 4.2 cerbera which caused his car to misfire and cat to overheat(glowing red and spitting glowing bits out of the exhaust)i think this was a mixture sensor and only affected one side of the engine.would this be the maf?

That's surprising, I was told TVR are extremely reliable cars.
[img]images/graemlins/jump.gif[/img]
Eric

I doubt it was the maf - more likely one of the lambda sensors or the knock sensor.

A bit of a long winded explanation this, and maybe uncalled for, but here goes [img]images/graemlins/wink.gif[/img]

Think of the maf as a replacement carburettor.
In a carburettor it meters fuel based on the amount of air being allowed to pass through, which is essentially how far open the throttle butterfly is (which is the bit the throttle pedal normally actuates).

In a car with fuel injection the engine management needs to know the amount of air flow so it can 'inject' the correct amount of fuel to maintain the correct mixture.

You could simply have a butterfly with a position sensor on it (most cars still do, unless they are drive by wire), but that only gives a throttle position, and not airflow (which changes with rpm and load), so would not meet the strict emissions.

One type of maf (Mass Air Flow meter) is a bit like a hot wire. As the air passes the hot wire it is cooled, and this cooling subtly changes its resistence. The change in resistence is proportional to the air flow, which in turn is proportional to the engine load & rpm.

If the maf fails for whatever reason the engine management will go into a 'get you home' mode, and will report a fault code.
What it does then is meters fuel based purely on engine rpms and throttle position. This can result in over or under fueling, which can destroy the cats.

The Lambda probe in the exhaust is also used to control the amount of fuel delivered, and when these fail it normally results in too much fuel being injected, especially when the engne is cold. The result of this is to allow unburnt fuel to enter the cat, which makes it overheat, and eventually melt !

Sorry guys, but work is a bit boring this morning [img]images/graemlins/tongue.gif[/img] [img]images/graemlins/spineyes.gif[/img]

Cheers,
John.

thanks for the explanation.
the tvr does have 2 throttle pot sensors which are from a ford engine and go wrong regularly however the problem sensor i think was on one of the downpipes or cats.
as for reliability it doesn't use oil as they are supposed to but he only had it two days before the cats overheated and had to have it transported to tvr.and now he has found out the springs are knackered,aparently they sag and require changing [img]images/graemlins/jump.gif[/img] [img]images/graemlins/rs4-button.jpg[/img]