A4 1.8T Avant - Should I buy it ???

[barneymagru]

Hi - Newbie here

looking for advice as I am about to purchase a 2003 1.8t with 80k for £3700. FSH from audi specialist and new coils and lambda sensors + belts and water pump at 55k. The seller has just informed me that the CAT is playing up and the emissions light comes on occasionally. He has offered to replace it for £200.

Is it normal for the CAT to go on a car with only 80K?

Any advice??

 

[AlexGSi2000]

Catalysts usually fail when the fuel mixture is too rich - typically caused by overfueling - this can be caused by;
Faulty MAF, lambda or injector.

Catalysts can also collapse internally.

 

[hades-]

your buying it ?
and hes trying to charge you to have it replaced
sneeky

 

[barneymagru]

your buying it ?
and hes trying to charge you to have it replaced
sneeky

he has been upfront to some degree - he has offered me £200 off the price if I get the job done myself.

Do you think I can get a replacement for £200 incl fitting? Do you think he is trying to pull a fast one due to the difficulty in removing the old CAT.

Like everyone else I am wary of buying a pup.

 

[Ian-83]

£200 for a cat sounds like a pattern one which from my experience pattern exhaust parts fit like a glove on a chickens lip! You be better off looking to see how much a sport's cat is or get a price from Audi for a genuine one.

Also if the cat has failed you need to be fixing the fault that caused it to fail first not just chucking a new one on. Sounds like it has a fueling issue to me. Either the 1.8T favorite air leak or it's possibly running rich.

 

[barneymagru]

the car has had 4 coils packs, MAF and rear lambda replaced in the last 12 months. Could the failure of these items caused the damage to the CAT. What is the air leak and is it easy to fix?

 

[Ian-83]

Those three items could contribute to the death of the cat. As for air leak it's hard to say what it could be on a 1.8T without physically looking at the car. Could be a small vacuum hose split, if not one of the hoses for the crankcase breather system could be split, could be a small split in a boost hose or the intercooler, could be one of the breather valves fautly. The usual suspect are the large amount of breather hoses under the inlet manifold and the vacuum hoses go brittle and split too.

I am not saying the car has one but at about 80k it's when breather hoses start to fall apart on 1.8T;s

 

[pauldazzle]

Coil pack failure could easily have caused the CAT to fail as unburnt fuel entering the CAT will quickly kill it.
As already stated split boost/vacuum pipes is a really common failure, & can be difficult to pin down without doing a smoke test.
Easy way to check you have vacuum is to pull one of vacuum pipes off & if you have vacuum it'll hiss as you disconnect it, also if you put your finger over it with the engine running you should be able to feel it sucking in. If it does neither you have split somewhere.