Hi all, I’ve just purchased a 2015 Q7 sports edition, the high pressure fuel pump let go, it’s booked in on the 10th March with a worse case of new pump, injectors and flush through the fuel lines for £4200, it’s done 90,000 and has the 3.0tdi, slight tap on start up (when it started) so timing chain noise potentially, I’m planning a gearbox flush service is there anything else you would recommend that I do as preventive maintenance

 

I guess the question is do you have any recourse with the seller; any limited warranty contract provided with bill of sale, etc.? That's an awful lot in repair costs you are about to incur on a car you may have just paid a fair price for. If you have made the appointment with an Audi dealer, prepare to bend over, as well as hand over your wallet. Never take the car to Audi for repairs outside of warranty/factory recalls. Use a good, independent shop that knows German cars, and buy yourself at least a basic, VAG-compatible diagnostic scantool (OBD-Eleven, etc.) that will be able to show you stored trouble codes you don't see on the dashboard lights.

To own an older Audi requires some knowledge of DIY...not super difficult stuff, a few basic, but specific tools (triple-square socket set) and scantool specifically able to read Volkswagen Auto Group cars (VAG). If you fancy DIY, get a VCDS cable to gain the access you will need to use Ross-Tech software/diagnostic tool with your Audi. If you care not for DIY, then you'll be spending quite a lot on shop charges for this car. The HPFP fragging itself is not an easy repair, as it may have contaminated everything in the fuel loop, but in general, maintaining your Q7 is no more difficult than any other car, if you stay up on your maintenance items.

Start by doing a level reset on maintenance....all filters & old fluids get changed, and drain/fill service on transmission. That means your neglected driveline fluids too; front/rear differentials, transfer case, transmission...all the items Audi has never serviced on the car. When changing oil, do oil flush and bottom drain it fully to get out any build-up and accumulated varnish, then use a high-quality oil such as Liqui Moly meeting the VW oil spec for your engine. Recommend Ceratec engine additive if you plan to keep it long-term. You may want to shop FCP EURO, or similar parts sites that offer kits to do a complete annual maintenance. Pay strict attention to using the correct fluids.

 

Thank you so much for your reply, this is my wife’s car and she really wanted it so I’m going to do my best to get it all sorted for her, there is no recourse on the seller, it was a private sale and it’s one of those things which you can’t know is about to break, the £4200 will cover the complete flush of the fuel loop as well. Is it worth renewing the cam chain as it’s a little noisy on start up and might there be a labour saving doing it at the same time as the fuel work, once it’s all working again I will get the gearbox service done as well.

 

I’d get another opinion on the tranny fluid. Have heard from two Audi independent mechanics not to change the fluid. They have seen trannys fail afterwards. Was it just coincidence? That I do not know.

2008 Q7 Premium
3.6 engine
201,000 miles

 

The HPFP repair is going to get expensive, no doubt about it. Timing chains are an 'engine-out' procedure on this car, which easily outpaces the cost of the HPFP, and they are unrelated services. Your car is so very low mileage that all you need to do is run an oil flush product through it prior to changing oil out. I'd go with the Liqui Moly (LM) oil flush, LM Ceratec, LM motor oil (meeting your engine spec), as this combo will clean it out (level-set), protect & preserve, and increase economy. My cars run noticeably quieter on the LM oil, than on either Castrol Edge or VW/Audi branded oils I've used prior, and I won't be using either of those 'recommended' oils ever again in our Q7s. Not to say you'll never hear a bit of rattle at start-up, especially in colder weather, but mine is minimized and often unnoticeable at start-up now, and both have more than double the mileage you have on your Q7. That said, if your start-noise rattle is shockingly bad, loud, continues on or morphs into a constant chatter as car idles/runs, or seems otherwise scary or abnormal, get a trusted local mechanic's opinion on it.

Transmission: Never power-flush the transmission; do a standard drain/fill service, which gets close to half of the fluid capacity out of the car, and allows you to evaluate the condition of the remaining fluid in the system. Going to the extreme in removing all the old fluid, or attempting to 'flush' the system out can both have immediate/short/long-term detrimental, and unintended impacts. The goal is really just to get some new lubricant into the system and evaluate the old fluid for contamination, particles, grittiness factor, etc. The new fluid buffers and improves the quality of the remaining fluid in the transmission (approx 13L overall capacity). This transmission and it's attached cooling system holds a lot of fluid, and it has high-quality, full synthetic ATF from the factory, so it's just fine to do a drain/fill service on it and bolster the older fluid with new fluid added, especially on a car with low mileage, like yours. My strategy was to pay a shop to drop the pan/replace gasket & filter, and drain out as much of the old as would drain, but they both had a lot of miles and had never been serviced prior, so it was both preventative and level-setting on my part (they were noisy and shifting quality was off too). I sourced the parts & fluid, then paid my local garage to do the labor on it. I bought in bulk containers (2 X 10L containers of Liqui Moly ATF), so I'm already set up for the follow-on drain/fill service, which will further clarify and improve the overall quality of fluid remaining in the system, which was massively improved by the first service's replacing approx 2/3 of total fluid volume. If I had your wife's car with low miles, I'd just do the drain/fill type service, and then just keep doing drain/fill services on it at regular intervals (50-55k kilometers).

The rest of the driveline fluids are really fairly simple to change out (front/rear differentials, transfer case) and each holds approx 1L of fluid. There's a fill plug up top, and a drain plug at the bottom of each...not super difficult. I did those myself using a hand-pump. Either way you go, you can save a ton and ensure you get top-quality fluids/parts at a fair cost by sourcing your own fluids & parts...the DIY install is optional.

 

'10Q7TDI_Prestige' Not trying to hijack the thread....but i just bought a 2015 Q7 3.0T and couldn't more pleased with it. I have full records of dealership maintenance, but nothing otherwise. 139,000 on the clock and it drives like a new car. Just as you said and I have experienced as well with my past VAG vehicles, there has been no work done to the transmission at the dealership. I cannot answer to an inde or other shop though. So I am now trying to decide.....drain and fill, or drain, new filter, gasket and fill. This is the first 8 speed torque converter transmission that I have had and would say that it is noticeable how much it shifts. Do keep in mind that I have had dual clutch cars as well, so I listen to my cars as they speak to you and a person needs to listen. It shifts fine, nothing harsh about it but just noticeable when it does during normal driving. At any rate, if this were your new purchase, what would you do? FYI, I do all of my work on my cars unless it is something that definitely requires a lift and in that case, many times have paid my semi-retired VAG friend mechanic to use his lift and space. He is currently in Florida on an all winter vacation and I respect his time. The last thing he wants to here is my car crap. Thanks in advance.

 

Does your Q have a hitch and more importantly does it have the 7 pin receiver next to the hitch?


If so, you can assume the car did some towing and I would definitely replace the fluid and filter. Both of my Q's had the hitch but not the plug receiver so if they did any towing in their life it was probably light duty and without trailer lights.
My first Q I changed the fluid and filter at ~85k miles and it looked brand new. Didn't smell or look burned, filter looked fine and there was nothing out of the ordinary on the magnets in the pan.
My second Q I have not changed yet (90k miles), but it shifts out of park into reverse much harsher than my other did so its going to get a filter and fluid change here soon.

Blau Parts has a good writeup on how to flush all the fluids, transmission, transfer case, and both diffs. Usually you can find the fluid cheaper (Toyota fluid) but the kits make it easy.
https://www.blauparts.com/blog/audi-...08c-aisin.html

 

If I had 139k miles with no leaks or major noise/rough-shift issues, then I'd advocate you just do the basic drain/fill service on the tranny, so you can verify the condition of the fluid that comes out, etc. Bear in mind, the overall system capacity approaches 13 liters of fluid.
FACT: The specs on the OE fluid say it falls below the required transmission fluid specifications when it hits 100k miles in the car; no ifs, ands, or buts. Both my cars transmissions were noisy and shift quality degraded by 95k miles. Q7's with the factory trailer/tow package have a higher capacity radiator, higher capacity cooling fan, and special fan shroud installed to optimize cooling performance, which in-turn helps preserve both engine & transmission fluids from getting 'cooked' during high heat loading, such as when towing, climbing mountain passes, and other types of 'zoom-zoom' activities. You don't know anything about how the car was driven, so pay attention to if it has the factory tow kit or not (dealer can print or email you the original window sticker), and be sure there are no signs of leakage at the tranny sump. The Q7 is very well insulated; be sure to drive the car with windows down to be able to hear any transmission noises/whining, or other undesirables that may be present.

What we know for sure is the OE fluid is not designed to last past 100k miles in the car. The drain/fill procedure will net you a few less liters than dropping the pan out, but it's a good for diagnostic and all you need is fluid/fluid pump, etc. If fluid looked/smelled burnt, then you could change course, if need be, or just do another drain/fill service on it at earliest convenience to continue to improve the overall quality, lubricity, smoothness, and thermal protection the new fluid provides the transmission.

Audi Service Departments tell owners it is a 'sealed' system with "lifetime fluid", which is 100% B.S., unless you define the expected lifetime of the component as 100k miles. Naysayers who drank the Audi advertising 'kool-aid' should go read the maintenance recommendations provided by Aisin, the manufacturer of this 8-speed tranny. Aisin states doing fluid services at regular intervals on this transmission is required from it's in-service date to keep it working properly and protect the internals, just as you would expect.

 

Thanks so much for the reply. As much as I would like to tow an occasional thing. This one does not have the hitch or tow package. I think that is a a great thing knowing that it hasn't been abused by towing. I like the way you think as it was my thoughts exactly....to do a drain and fill to give it the sniff and looksie test. Depending on that, I may change the filter on a future service. Thanks again. Really appreciate it.