I’ve had a good dig-around Mick, but with little success, so here are a few tips. Audi A6 quattros always used the older Tiptronic transmission, which is good news for you. Fluid and filter changes are not cheap, but still a lot cheaper than total replacement or rebuild of a Tiptronic unit. Much depends on the mileage, but it might be wise to find an automatic transmission specialist in your area and have a chat with them. Aside from regular oil services (mostly to protect the cam drive chain, but also general engine wear), the problem areas are the inlet manifold swirl flaps, water pump failure, and problems with the watercooled exhaust gas recirculation (EGR) unit – in the form of coolant loss.
Most swirl flap problems on all the cars that have used them (BMW, Vauxhall, and others) come from a general gunging up of the system, much the same as happens with EGR valves, due to short runs, lack of frequent oil changes, and sometimes cheap fuel without good detergent additives. If the swirl flaps and their motorised drive unit fail, you’re looking at three figure replacement costs. So if you have any doubts about whether the car has been serviced regularly, and properly, this is another reason to start with an oil and filter change. You can remove and strip down the manifold to have a look at what’s inside, but it’s pretty advanced DIY and maybe best left to a well respected Audi specialist, one of which you should try and find, and befriend, in your area.
I am informed that Audi/VW brought out a relatively inexpensive swirl flap repair kit following the exposure of these problems, but a couple of hours of Audi garage labour could still end up in a painful bill! Regarding the EGR unit, see if you can identify it, and keep an eye out for any suggestion of leaks, and suspect the EGR area if you start getting poor engine performance and/or poor fuel economy. Water pumps often get replaced along with cam belts, but since you don’t have a cam belt, I doubt if it (the water pump) has been replaced. It is worth asking a specialist for advice on this – the pump is cheap enough, but the labour to strip the engine down and replace it is significant! I hope these few pointers assist you, but do let me know how you get on. Sounds like you’ve just bought a car and want to keep it in good nick. Let’s hope that you’re starting out from a good place, and not with a neglected engine!
To which Mick replied…
Doc, thanks very much for the information. I’ve had the car for around 15 months and already done the basic oil and filter changes. It supposedly had a full Audi service history when I got it from a local non-franchised garage, but when I asked for print-outs or similar from Audi, it all went quiet and nothing was forthcoming. (A call to Audi Customer Service should sort this. Doc.)
Generally, I have done all my servicing and repairs for some decades, but I’m finding it progressively more difficult to find the relevant information, hence my e-mail. (Aren’t we all – all diagnostics and little practical maintenance and repair information. Doc.) I spent a good hour yesterday replacing the offside dipped headlamp bulb – needing the air filter, air mass meter etc. all taking out for access! I was hoping to track down a full service schedule and tips – .e.g. on how to get round the electronic parking brake for brake servicing etc., I’ve picked up on the manifold problem on various forums in my quest for ABS and ESR warning light diagnostics (thinking it might be the dreaded Teves ABS unit fault, but it turned out to be just a sensor, (Phew! Doc.) after paying for more diagnostics as my code reader doesn’t read ABS faults). I have now located an ex-VAG mechanic in nearby Morpeth, and he seems competent, but very busy, which says something! I asked him about DIY on rear discs and pads and was told “you need my computer to set/reset your electronic parking brake”, inferring that it’s not a feasible proposition.
Surely one of the magazines must have covered these cars at sometime? The net is awash with blogs/forums, but they’re generally infuriating and so badly written and user unfriendly! Thanks again – if turn anything up, please let me know!