Magnet

OK, so the seems you have a significant problem on one cylinder, and since your mate has a garage then I would have thought it would not be too much of an issue to remove the cylinder head and the one piston to assess the problem - assuming this has not been done. if it has been done then you will know what the plan of action will be, which might be reboring this cylinder and fitting a new piston etc. Can we assume there hasn't been an oil pressure problem with this engine ( high oil consumption sometimes leads to low oil levels and low pressure). It seems you are in a fortunate position of having a mate in a garage, and if attending to the one cylinder is not going to be the full answer then it might be worth looking at a second hand engine as an alternative to rebuilding yours. Kind regards, Gareth.

Hello Mark, Sorry to hear of your problem. I think it might help if we know what damage has been caused to this engine and how. It should then be clearer what work will be needed. Kind regards, Gareth.

Hello Alan, Without being patronising, it would seem to know your way around a volt/continuity meter, so I guess you should be off to a good start. If we start with your last mentioned issue - the battery is draining. To me this would be my first port of call, and I would want to find out why, before I worry too much about the roof not working. Maybe part of the same problem, but maybe it is, until it is proved to be. To do this you will need a more sophisticated meter than your average DC/AC volts and resistance meter, since you will be measuring currents and likely to be subjecting the meter to greater currents than the mA most meters will handle. Blown meter will be the result otherwise! The logic is simple - you connect a lowish current amp meter between the removed negative lead and the batery post (switch off your interior lights etc. ) and measure the current taken after the alarm has 'gone to sleep'. This should be mA, but if the battety is draining then it will be higher. Now remove each fuse in turn until you lose the current drain. That will be the fused curcuit which is at fault, and you will now need to find the fault in that curcuit. It could quite possibly be the roof curcuit, but you need to confirm or refute that before assuming. Back to the roof issue:- I would have a guess ( and a guess it would be) that your 'shorting' problem is in the section of harness that gets flexed when the boot is opened and closed. I appreciate you have tested it but such areas are notorious for cracking insulation as the harness continually flexes over the years. Obviuosly this time if year is worse as the harness hardens in the cold weather. Good luck with your checking, but very often such annoying faults are worth an investment of a couple of hours with a local trusted auto electrician. Kind regards, Gareth.

Hello Rob, Well spotted in noticing this issue. If it were me, I would be proceeding from here with caution, since this car obviously has a known problem and I think it is not unusual for all cars of this age will have (further) faults which might not manifest themselves until it is purchased and used. I would guess it goes as read that this car is not being sold by an Audi dealership ( too old), but can we take it it is being sold at a used car lot - or is it a private sale? My first port of call would be to inspect the V5 and find out how long the last keeper has owned it. Short ownership? bad sign - walk away quickly. If a reasonable period of ownership then I would be contacting the owner and have a chat about their experience of the car. If it's a private sale then I would again walk away unless it is very cheap and you are prepared to spend money. Back to the problem:- could be one or more suspect injectors ( at c £150 each - don't quote me, could be more or less), or possibly water entering a cylinder via a faulty head gasket or similar. Full service history is fine, but it certainly is not the be all and end all of any guarantee of freedom from mechanical issues. Good luck with whatever you decide to do. Kind regards, Gareth.

Hello Shalin, Has this car been in for an emissions recall by any chance? Kind regards, Gareth.

Hello Rob, Very pleased to hear your advanced exciting news. Just wondered if you really were actually going to have this car registered prior to 1st January since technically, it will otherwise be a year old within 3 weeks of you owning it. I appreciate the dealer will tell you it's ongoing value will not be affected, and a 67 plate vehicle is a 67 plate despite it being late 2017 or 2018 registered !?? But....... Dealers clap their hands at being able to register vehicles during the quiet month of December, so it might be worth bearing this in mind to make sure you get totally unbiased advice. If it were mine, there would be no second thoughts about waiting for Father Christmas to arrange its delivery a week after Christmas. Enjoy - and sometimes the enjoyment is greater if you have to wait a little. Think about studying the brochure on Christmas Day - in anticipation! Kind regards, Gareth.

Hello Richard, To get your head around this issue its worth bearing in mind that you are getting yourself in a twist about a debatable 15 thousands of one inch! i.e. your quoted 0.4mm difference between front and rear treads. A !Removed! paper as we used to say. Now in theory you can run the fronts down to an even 1.6 mm remaining, but come what may, you will need to bite the bullet and renew the set since you will otherwise be at the worse possible case of maximum tread on the front and minimum tread on the rears until you change the rears some weeks later. Kind regards, Gareth. Whats wrong with the three letter word "!Removed!" then?

ZHello Illya, I'm not sure how much of this is going to be of positive help, but I think you are doing the right think in going your homework. Appreciating these (6?) stack CD changers may have been able to have been fitted in the glove box on this particular model, it was not uncommon for them to have been fitted in the boot or even under the passenger seat when they were in vogue. In my experience, these units can be unreliable in service and can tend to jam - boots and even inside convertibles can be a harsh environment. You could be lucky, but worth bearing in mind. Yes, there will be a dedicated connection lead designed to fit back into your existing original equipment. I seem to recall Alpine was a volume brand for these. Now certainly not my field of expertise! - but I'm sure there are many members on here who will advise you - but have you thought about the more up to date and comprehensive, and probably more reliable ways of downloading music into the car, rather than playing CDs. Good luck with it, Kind regards, Gareth.

Hello Richard, The theory is that out cannot renovate 'modern car' leather since it is lacquer coated - unlike the leather on cars of some 20 years plus age. Having said that, I have used leather cleaner on a non-Audi car with some favourable results, and the products I used were by the well respected Autoglym group, who's polishes I also use. They do a cleaner and a conditioner, and it's really up to you to decide if the conditioner is required, since if the theory applies, you are only conditioning the lacquer layer! There are obviuosly other products available and one that comes to mind is by Poorboys? ( American origin?) - seems to be well respected by some. Hopefully, you will receive other replies and recommendations on here, but you might also like to look on other forums - try Jaguar and Volvo for a start. Kind regards, Gareth.

Many thanks Dave, Always good to have the correct angle on these things. Kind regards, Gareth.

Can someone confirm or refute this :- I was in with my local ( local chain) tyre depot yesterday and the subject of batteries came, up with the 25 years-employed-with-them, manager. He told me that the battery on the Q7 was under the seat (passenger?) and to replace the battery, the seat and associated air bags have to be removed in order to change it. He recons on it being up to an 8 hour job when everything is taken into account. Is this correct, and at main dealer hourly rates who would you arrange a mortgage with!? I like learning of things I don't know about, but it would be reassuring to have some expert independent opinion since it sounds rather unbelievable. Kind regards, Gareth.

Hello Rob, Unfortunately I cannot agree with Steve's normally sound logic on this occasion when it is suggested it must be the tyres. Hindsight ....... as they say......, but you have changed two things here at the same time, tyres and wheel alignment set up, so the sudden cause of your tram lining could be due to either (or both). My book may be considered old fashioned, but I always try to change one thing at a time, and test that change before moving on to stage two change. For example, in these days of fault codes being king, the existence of two codes usually tempts the technician to change the two listed components and then he doesn't have a clue as which component was at fault, and it was quite likely that two codes showed up on a 'cause and effect ' logic. i.e one component affects the other, but the other may not actually be at fault. Anyway Rob, apologies for continuing my pessimistic response on this, wheel alignment equipment is now state of the art and capable of measuring minute out-of -alignment. Problem is, it's always down to the 'technician's' ability to interpret the data and more importantly know exactly what he is doing when he adjusts something. So, is the wheel alignment now set incorrectly?? Answer - we don't really know - so you need to get this independently checked by someone who comes with a recommendation, and that recommendation may come from say a local Audi independent. Worth an ask. Yes, could be the tyres. Is it possible to swop fronts and backs on these? If so, that would be worth a try. Daft question perhaps, but have you checked that the direction of rotation is correct? Yes, I know they should know and check that they have the correctly tyred wheel on the right side (and they probably have) but worth having a check yourself. Goid luck with it Rob, Kind regards, Gareth.

Hello Wayne, I would agree with Cliff, and it's quite possible that the two symptoms are not connected. Re white smoke and not staring as well as it should ( smell of diesel as well?) could well be problems with one or more injectors, and this can be checked via. a leak-back test. If it were mine, I would be getting this done st a local and trusted diesel specialist. Again, I'm with Cliff on the water loss logic, and getting a system pressure test would be the best starting point. Re. compression test, you would need to be aware that diesels run on high compression pressures compared with petrol engines. If there is a head gasket issue between a cylinder and a coolant channel, it will not necessarily show up on this test since the relative compression pressure loss may be too small to assess. Kind regards, Gareth.

Hello Abby, Is the car getting up to temperature reasonably quickly and then holding that (normal) temperature under all driving conditions? On the check the simple things first principle, have you checked the tyre pressures? You say the tyres are good but.... Kind regards, Gareth.

Hello Tim, Of course, it's of no compensation to you, but if you read the numerous tales of woe on here, it could be said that you have got off lightly. Glow plug problem? Well these can give problems, but the problems tend to manifest themselves when the temperature falls and you may notice a greater reluctance towards easy starting. OK, never had a problem with them before - and low mileage - but I think it's becoming a fact of life that some components of the electrical equipment can become unreliable on an age basis rather than a mileage basis. Kind regards, Gareth.

Hello Chris, What grade of oil are you running the car on, and as a matter of interest, what brand. Oil pressures with oil at operating temperature? Temperature important as I say. As a rule of thumb, I would have thought not less than 40psi at 2500rpm and above, and hopefully not much less than 20psi at idle. Others more knowledgeable on this particular engine may suggest other figures. Interesting to know what figures you get Chris and what the oil is. Kind regards, Gareth.

Hello Abby, Before investing your money in magic carbon cleaning systems, I would start by checking and replacing the air filter with a good quality replacement unless you know this has already been done. Always a good insurance. As always, don't go for the cheapest - go for the best at the most competitive price. Kind regards, Gareth.

Hello Chris, I notice your mechanic friend is now suggesting that this needs connecting to an oil pressure gauge to actually measure the pressure. To me, this would have been the first port of call, since sensors and associated wiring can give spurious warnings even when the pressure is correct. As you probably know, true oil pressure should only be checked after a run of about 10 miles - when the oil is up to operating temperature. Some, incorrectly assume, that when the coolant is up to temperature, the true operating oil pressure will be achieved. Wherever possible, a car should be test driven over 10 miles to check is if oil pressure light does flick on on idle. I am unsure whether your sitting on the drive testing is after such a run, and if so, it might point to a connection problem where car movement influences the connection. Anyway, an oil pressure test it needs. Kind regards, Gareth.

Hello Richard, This is not uncommon - as you are finding out! Such issues will become more troublesome as we move into winter and the wires become more brittle. Kind regards, Gareth.

Hello Abby, The labour charge would seem to be very reasonable to me. As for the parts, you can go down the route of cheapest will do, and take a chance on the components lasting - which would not be my approach if it were my car. I would be shopping around for good quality parts at the the best prices, and if not using VAG parts (available at discount) then I would only consider LUK clutch parts as an aftermarket alternative. Other aftermarket makes may be cheaper, but... In the long run...? Kind regards, Gareth.

Hello Peter, You are very welcome. Battery and should be checked at service?? Um - in reality, only if there were obvious reasons at the time to suspect it wasn't serviceable. Are you sure they alway check your tyre pressures for example? - they should but......! If it were mine, I would simply be doing what you suggest and charging the battery overnight and taking it to either a good auto electrician or Halfords an getting the battery efficiency checked. If it is found to be sub standard then if you respect your wallet, you may be wise to check alternative prices to Halfords. I have used Battety Megastore at Tewskesbury (no connection and there are others -e.g.Tayna etc.) , but I always buy batteries which have at least a 4 year guarantee - Varta amongst others. I think you will find prices are reasonable. Brake light switch. It may not be as simple as checking if the brake lights work and assuming if they do, that the switch is 100% serviceable. Anyway Peter, Battety check first I think. Kind regards, Gareth.

Hello Steve, Worth pointing anyone who is thinking about subjecting their vehicle for an emissions recall to read the comments under that heading on this forum?? Kind regards, Gareth.

Hello Peter, I could be barking up wrong trees here but with all electrical faults, I always first eliminate the battery by getting it tested under load. Appreciating this vehicle is only 6 years old, you would not expect the (original?) battery to be suspect, but I am unsure of the life expectancy of batteries subjected to the stop start system. Apologies if your garage has (definitely) elininated this possibility. If you do indeed eliminate the battery, it might well be worth looking at the brake (light) switch, which I believe plays an important part in the operation of the stop/start system. Kind regards, Gareth.

Hello Andrew, I could be wrong, but I wonder whether the test you had done was by a qualified auto electrician rather than a dab-a-meter-on-it mechanic. An auto elect. should have been able to have a good stab at actually identifying the problem such as a diode, regulator etc. and judging by the c£300 alternative, i would consider the anticipated cost of sorting yours out would make this an economical route. Kind regards, Gareth.

Hello Andrew, Sorry to hear of your believed alternator issue. If it were mine I would be getting a simple test done on this and the charging system in general, by an auto electrician - should be quite cheap- before deciding to replace the alternator. Alternators are generally long lived and issues can very often be corrected economically by replacing some of the components rather than fitting an exchange unit. I'm judging you will be looking for a secondhand comparable replacement, which is one option, but I have often said that as far as secondhand units are concerned you have to remember "you could be buying your own (faulty) one" , so it's probably better to get your own fixed if it is indeed at fault. Kind regards, Gareth.