Bigdave1230

I’m inclined to think it’s possibly an ecu fault. I suspect when you loosen an injector pipe and crank that you’ll get a diesel but might seem a little bubbly making you think it’s drawing air in and lead you into an expensive world of changing components on the fuel system. I would look for a local independent mobile auto electrician to come and test the ecu etc. Should only cost a callout and be less than £100 and might save a lot of chasing. Alternatively you can send the ecu away to be checked/repaired 🤔 there used to be a company on the internet ecutesting.com that charged about £250 to repair/exchange them but if no fault was found then they refunded and sent back but you have to pay about £20 postage. I’ve had a similar fault like this before and it got very expensive to chase and sort. ( it was the ecu in the end but I only found this out after about 2k into it 🤦🏻‍♂️). Theres a post about it with all the symptoms somewhere earlier in the forum posts.

Hi did the car cut out when driving or simply not start one morning? Did the glow plug light flash at any point?

👍🏻

Crankshaft sensor. I’ve had that fault before. Won’t have any fault codes stored either.

Saw something similar a few years ago. Turned out to be the starter motor. It would start when cold but cranked a little slower than it should but once the car was warm it wouldn’t even crank until cooled.

I’m tempted to think it’s possibly a sticking/fault turbo wastegate but I’d of thought it would have thrown a code for boost pressure negative deviation or something similar.. Does it do the same thing on idle if you rev it or is it just when under load in gear?

2007 did around 18mpg not 180bhp! Auto correct 🤦🏻‍♂️

I get around 23mpg on average around where I live which is quite hilly with most days the car not doing more than 5-6 miles but on a run it’s easily over 30mpg. I had a 2007 which used to do around 180bhp where I live but I’d put this down to it having the 6 speed gear box instead of the 8 speed which cars after 2011 have and the engine not being as refined. 2014 seems to be the sweet spot for the 3.0 245bhp but like all cars there are exceptions. I’d say avoid cars without a religiously followed service history as sporadic history is usually a sign that the owner couldn’t really afford to maintain it and has opted to repair when things wear out. Common stuff to check Water level - if low take the engine cover off and check on top of the engine in the vee for smell/signs of coolant. It’s common for it to leak under the dpf cooler which is around £400 to fix as it’s a pain to get to. Suspension - lower the car to its lowest setting the raise it up to lift. It should raise quickly and without being noisy in the cabin. Usually if there’s a problem it will show itself doing this by the display greying out and a suspension light showing on the dash. Most of the time it’s the compressor at fault which costs the moon from Audi but copy’s can be bought from eBay and isn’t a big job to fit. Make sure it doesn’t clunk over bumps or pull on the road when letting go of the steering wheel or under braking. It’s usually worn lower arm rear bushes which can seize in the bush sleeve and be a pig to get out. Not expensive but awkward if not on a ramp. I have Pirelli pzero tyres on mine which have done nearly 15000 miles and don’t need replacing. I run them with about 42psi which seems to stop them wearing on the outer edges. My mate ran his on less and did a set in 8000 miles so we all run on 42psi. Unlike Land Rover it only has 1 battery which does generally last around 5-6 years before getting tired. Check in the display settings if the daytime running lights have been turned off and the time the lights stay on after the car has been locked has been set to zero as someone trying to hide the fact it needs a battery will have done this. Turn the lights on and the heater on then after about 10-15 seconds try and start it. It should fire straight up within a second without any hesitation l. Also a failing battery will disable start stop. About £300 for a battery and about 45 mins to do it’s under the passenger seat. Heated drivers seat usually never works and is a good haggle point. It’s a common problem that the element break’s usually from a wallet in the back pocket or from kneeling on the seat. Not the end of the world if your not fussed but Audi want £600 to sort it. probably a few other stuff but I can’t think of anymore for the min. I’ve had 4 of them now and once you’ve had one it’s very hard to find something else 7 seater that ticks as many boxes as it does. I’d say 2014, under 80000 miles, full service history, panoramic sunroof is a must, and check general condition inside and out. If something doesn’t seem right for what the owner is saying then walk away as there’s loads of them out there for sale.

Try putting a jump lead cable from the negative terminal under the bonnet or from the battery negative onto a good metal point direct on the engine and try starting it to rule out a bad earth.

Under what circumstances does it stall? As in cut out under acceleration or stall when stationary etc. Do you get any warning lights (glow plug light flashing etc). Are there any messages stored in a scan?

Might sound odd but does the rear windscreen washer spray onto the rear window? The rear wiper motor is designed stupidly to have the water run through the motor itself. The motor seals fail and when trying to spray water onto the rear screen you can hear the washer motor and the rear wiper moves but little to no water comes out. The water runs down the inside of the tailgate onto the light unit and corrodes it over time so if you just put a multimeter onto the terminals where the bulb goes it will show no power. Might be worth a check before anything else.

LED lights around the headlight and the indicator strip is LED

From memory the facelift happened in 2009 with the main difference being LED lights front and rear. That definitely doesn’t have LED lights. The next facelift year was 2011 where the bumper design changed slightly and the engine had a slight tweak for the emissions which resulted in a bit more power too. The gearbox changed from a 6 speed to an 8 speed.

Depends what options were on both cars. The screen will be coded to the original car so if you do a code check it will probably say something like “control head locked” or similar and from memory the voice control button on the steering wheel won’t work. If you still have the S6 screen in then you can change the boot logo to Q7 and it’s highly likely that the air suspension option isn’t enabled as I don’t think the S6 had air suspension. If you have access to vcds you need to enable the green screen option to get into the options menu on the mmi. It’s possible that on a 2007 car that somebody might of already enabled the menu. Press car and setup/menu together for about 5 seconds and see if the green menu comes on the screen. If it does then Google or YouTube what you’re looking for before just playing around in there as some things can’t be undone if changed.

No clutch to worry about it’s an automatic so has a torque converter. Depending on what engine variant you have ie 215bhp/272bhp then your existing torque will be 500nm or 600nm. Has the remap place quoted any bhp and torque figures? The SQ7 gearbox is rated at 1000nm. Not sure if it’s the same gearbox but if not it’s probably the 8HP70 which is rated at 700nm. If you can find out what variant is in yours (by either ringing Audi or doing a parts check using your reg) then the last numbers are the torque rating. ie ZF8HP55 = 550nm , ZF8HP70 = 700nm , ZF8HP90 = 900nm for a petrol engine and 1000nm for a diesel engine.

Passenger front wheel

Passenger side wheel off and remove the inner wheel arch liner. You can do tests on it in vcds if it’s misbehaving. Common problem is them locking on older cars and the fan randomly operating on them overnight and flattens the battery overnight. You can remove the fuse for it in the car if it’s causing a problem.

Did it work one day and then not the next or was it doing the run for 5 mins then cut out 5 times with the flashing glow plug light of death?

When you say oil spitting out of the tappet covers do you mean both side of the engine? Did it run and drive ok or was it struggling to idle or seem low on power? Will the car turn over and not start or will it not turn over now? Have you checked the both the coolant level and the oil level? Is there any strange smells coming from the engine bay ie fuel or coolant? How many miles has it done?

Power flex sell the bushes separately but if your replacing either the arm or the bush and doing it yourself it’s worth getting a replacement bolt that goes through the rear bush as the bush sleeve and bolt corrode together resulting in the bolt not sliding out and needing heating or cutting out. The bolt has an elongated washer on it that adjusts for wheel alignment so needs marking up with tipex or similar otherwise it won’t drive properly after refitting.

Does it go up when you start the car or just stay on the ground? Check the level sensor hasn’t popped out of the upper control arm. It just a piece of plastic that clips in

👍🏻 Glad you got it sorted! Mine ended up costing about £1200 in bits to fix in the end 😬

I sent my ecu to a company called ecutesting.com. They had good reviews and was about £220 to repair including postage. They confirmed it was faulty and do an exchange included but unfortunately they didn’t have one like mine in stock so refunded my money and sent it back. So it ended up being a free diagnosis. I then got a secondhand one and got it cloned. The ecu is a bit of a pain to take off as you have to grind the cradle it’s in as the bolts have no heads to unbolt off.

There’s a post about it from about may last year if you look back through the posts

Same thing happened to my 2007 q7. Glow plug light started flashing but drove fine all the way home. Started it the day after and all was fine for around 500 yards then started flashing again then cut out. Would start straight up but drive 500 yard and cut out again. Then 200 yards then cut out until eventually it wouldn’t start it just turned over and over and not even try to start. No EML but had a code on vcds for an injector short to ground or something similar. Cleared the code but still wouldn’t start. Changed all 6 injectors ,high pressure fuel pump and fuel pressure regulator but still would just turn over and over. Turned out to be the ecu that had been spiked by a faulty injector. Bought a 2nd hand unit from eBay and got a mate of a mate to clone it to be the same as mine. Started first time after that.