Luey

Yes definitely seems much better. My worklist for the car is still pretty long however. This week I have to remove the inlet manifold and replace it. The swirl flap actuator broke off and it's bored a hole in the side the manifold. I'm going to replace the plastic one with a alloy one without swirl flaps from: http://www.darksidedevelopments.co.uk/ I've just blanked off the EGR system which I swear has made a noticeable difference too! I've just ordered some ZX1 like you suggested Dan, at some point I will probably do a full write up of my experience re-homing a Audi that needed just a little love.

So basically Quattro as I'm sure you're aware means the car is all wheel drive. The Haldex is basically a clutch at the rear of the car that engages and disengages power to the rear wheels. So for example if you're driving around town the car will only supply power to the front wheels, this reduces fuel consumption, among other things. Then when you put your foot down and the car needs that extra traction to apply all it's power to the ground it engages the rear wheels. Additionally if you can imagine your car off road, if the back wheels start to slip it'll disengage them and put the power to the front to pull you out the mud. I mean it's actually very scientific but I'm trying to give you a basic explanation. It requires a special fluid and a filter to operate and requires servicing usually every 40,000 miles (At least that's what mine needs check your own owners manual). I should say that a Haldex in order to avoid confusion is not the same thing as a rear differential. Some people get confused.

If it's from a dealership then you'll probably be a lot safer than a private sale. You should check the Haldex has either been serviced or get them to do it with the regular service. I would be considerably less worried if it has a warranty too, and it's not a high mileage car really. So I think you're pretty safe. Audi's own servicing is pretty price competitive now too: https://www.audi.co.uk/owners-area/servicing-maintenance-mot/fixed-price-services.html#/fixPrice?id=4&serviceCode=SERMIN

Yes my advice above stands true then

Assuming your profile it correct it's a Audi Q7 you're driving. Starter motor would obviously cause it to fail to start but if it's running wouldn't likely cause it to stop. I'm not sure who your breakdown cover is with but I wouldn't ever let anyone spray easy start into my engine. If you've got a large displacement engine, especially a diesel you likely won't start it again with a dead starter motor. It'd help if I knew what engine you have too, but I would hazard a guess it could be your fuel pump is on it's way out. That could certainly cause it to die on you and make it difficult to start. Otherwise my suggestion is to take it to a independent garage and get them to have a look.

You're going to have to give us more information. A car can cut out for any one of a thousand reasons.

I had another listen with headphones. It could very well be a misfire. It doesn't mean it's something too sinister however. As I said definitely go through the basics first. If you take us more audio we might be able to tell you more.

I absolutely love my Audi 2.0 TDI Quattro I would certainty recommend one. My experience with Audi's has generally been brilliant, they are certainly built to last. You really have to abuse or neglect one for them to start having big problems. Obviously check all the basics, tyres, brakes, clutch action. You can print of a pre-purchase checklist to go through online if it helps. The TDI engines are used in so many vehicles because they're very reliable and well designed. I love mine because it's pretty quick and yet I'm still driving about getting 40mpg or better. Do let us know if you buy it because I can give you some tip's to keep it running smoothly and avoid costly problems.

I would suggest going through the basics first. I too agree it could be something simple such as the exhaust rattling against something, a broken baffle is certainly a possibility. The exhaust is slung on rubber mounts, when the car is cold if you give it a shake you might be able to hear a broken baffle. When it's cold again with a thick glove you could also cover the exhaust (only for a moment) see if the sound stops. Anything inside the exhaust should in theory only rattle if there is airflow to move it.

The oil was definitely too low for starters and it was probably running a little dry. I did some reading online, modern gearboxes are incredibly sensitive to even minor discrepancies in oil level. I've added about 350ml which is more than I thought it was going to need but I'm sure it's got the right amount now. I'm really pleased with the end result, the gearbox is so incredibly smooth, the transformation is easily apparent. I'm going to do the transfer case and rear differential as soon as possible. I need to go buy some thinner pipe however. Audi say their gearboxes are a sealed system and don't need the oil changing but I would strongly recommend it anyway. The oil I removed was awful and I doubt at 10 years, 114,000 miles it was doing even 1/5th the job it was doing originally. I'm sure the transfer case will be just as bad when I go to do that too. I'm going to do my 184,000 mile Audi A4 next too, that's going to be fun.

I think I have it sorted now, thanks for the help everyone.

A vivid imagination could definitely be the case. I had read a few articles online that had made me very nervous about changing my gearbox oil before I even began. I don't think it's a lack of sawdust either, and yes I got exactly what you meant. I am the first to admit as gear oils go the stuff I have bought is by no means the best on the market. It is however the right spec and weight. I am sure this clean fresh cheap correct spec oil is better than the dirty disgusting 114,000 mile old oil anyway.

I appreciate the help. I've been looking into it for a couple hours. I have determined the oil is the correct weight and specification for the gearbox again admittedly a budget product. It is however 200ml short of specification. As I said in my original post, I am certain there is no damage done given the short gentle drive. I will be topping the oil up first thing in the morning. Then I will see where things go from there. I will at some point change the gearbox oil again for something expensive and premium. I will also have a look into a anti wear additive as you have suggested. I've used Lucas Oil Stabiliser before and found it to be brilliant. If anyone else has any thoughts or suggestions let me know.

I am hoping one of the wise members of this forum can help me out with a problem. I bought a 07 Audi A3 Quattro 2.0 TDI (170hp) a few months ago, it's seen 114,000 miles and had full service history until a year and a half ago. I decided to do a quick gearbox oil change as part of my maintenance plan. I wanted to get the gearbox back to that smooth buttery action you'd expect on a new car. I did the follow: There was no sign of any leakage from the gearbox. I drained the old gearbox oil without any issue or anything interesting to report. The oil was dirty, it came out the usual brown semi transparent colour. When it fully drained it was more or less black with a hint of blue in the drain pan. I didn't go through it with a magnet or filter it but there was no obvious sign of metal deposits that caught my eye. I filled up the gearbox with a fresh 2.1 litres of 75w90 Gearbox Oil I used some budget gearbox oil, which I have used before on other cars, I was/am intending to change it again in the future anyway. I took it for a casual and gentle test drive only a few miles and my gut was telling me something didn't seem right. The gear action was smooth and confident and much better than before which was really pleasing. However there was definitely a new faint noise bugging me. I will admit the sound was very faint from inside the car especially over the large and loud diesel engine. However winding down the windows as I drove along there was definitely a faint tone coming from the engine/gearbox area, I wouldn't describe it as a whine nor a grinding, more of a metal brushing on metal sound again admittedly very faint. I want to ensure everything is okay before any damage is done. Upon returning home very distressed and concerned I did some googling. I've read a couple conflicting reports about my gearbox in terms of oil grade and also quantity. I believe at this point the car requires 2.3 litres (0.2 litres more than I put in initially.) I wish I had measured what I had removed from the car at this point. Additionally I've read some conflicting reports over which grade I was/am supposed to use. If anyone could tell me where I can find or find me the actual spec it would be much appreciated. I plan on immediately topping the gearbox up to 2.3 litres before I drive it again. I'm incredibly confident that no damage has occurred from this mistake as I caught it so quickly. Can anyone give me any advice!