Audi Q7 (4L) 2005-2015

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With the first generation Audi Q7 you can tow things, transport things, travel long distances comfortably and even go to the forest for some mushrooms perhaps? Well you can, since it has a very good standard 4 wheel drive system but it’s definitely not a proper off-road car, obviously. It also shares the same but slightly modified platform with the first generation Porsche Cayenne and VW Touareg. But the Q7 is bigger than these cars and it was also available as a 7 seater version.

The interior with the standard equipment can look pretty bankrupt with the horrible looking standard MMI screen or standard fabric seats, but most of these cars are reasonably well equipped with navigation system, leather seats or blind spot monitoring system. And sometimes you can find also cars with wealthy looking full leather interior with the impressive 14 speaker Bang and Olufsen sound system, with heated and ventilated front seats and with all those other fancy features.

When it comes to build quality or materials quality, there are basically no big issues. All the plastic parts in the interior are fairly durable, so finding a car with worn plastic buttons is not that easy, but if you found one, then most probably the keyless start stop buttons or the windows switches will be worn out. + Some of the owners complained about a rattling sound from the rear-middle seats on bad quality roads. The panoramic sunroof can make various creaks or rattles as well, but other than this the interior is well built.

Possible problems

Let’s move on to the things which can fail more often:

-The first possible issue is related to the windscreen wipers. Interestingly the passenger side wiper arm can simply break which can be an unpleasant surprise during driving in the rain

-Then it’s good to check the keyless entry feature if the car is equipped with it, because the keyless sensors in the handles can fail. In this case you have to buy a new handle, or you can try to find a used one. But remember, that the faulty keyless entry handles can drain the battery

-The next thing on the list is the blower motor which can simply stop working. It’s located behind the glove box so replacing it is not very hard and there are videos on the internet how to replace it + you can save money if you buy a cheaper aftermarket part. But sometimes it’s enough to remove and clean the old motor

-The early cars made to 2007 can have issues with the regular non-LED taillights, which means that the bulbs in them will keep burning out or they simply won’t work, unless you replace the wiring harness. But some say, that it’s enough to pull the bottom contact in the bulb socket up, to make a firmer contact with the bottom of the bulb so you can try this in the first place

Check the electronically operated tailgate as well. If it’s not closing properly, then most probably the latch is faulty. The electronic motors are usually fine, but the gas struts obviously can get weaker over time

-You should also check if the rear windscreen wiper and washer system is working properly. The washer fluid should hit the rear windscreen with normal pressure, since the rear windscreen washer fluid line or the washer motor itself can leak as well

By the way, because of the position of the front cup holders, there are cases when owners simply spilled drinks onto the MMI control panel. And if this happens then the MMI system won’t work, so you have to change this control panel or just buy a new circuit board for the panel which is a much cheaper solution.

-And last but not least, there is the MMI multimedia system which can stop working, most of the time because of a failed amplifier which fails because of a well known water leak. So, as in the other cars, the water will cause premature death of some of the electronic modules and I don’t think you would like any of that!

There are basically 3 well known sources of water leaks into the interior:

-Let’s start with the easiest one which is related to clogged AC evaporator drain hose located under the glove box. If it’s clogged, the water will leak onto the passenger side carpet, but luckily it’s not hard to clean this drain hose. Just remove the plastic cover under the glove box, slide off the rubber tube, clean it with compressed air or with some edge trimmer line and that’s it.

-The next possible source of water leak are the clogged drains under the windshield, causing again, water in the front footwell. Basically, there is a rubber drain plug behind the front wheel well cover on both sides of the car. Dried out leaves and other junk can be trapped in these rubber inserts causing the water to accumulate in the scuttle panel area which will eventually leak into the interior. So occasionally just remove these rubber plugs and flush the area with water to avoid experiencing this very nice story.

-And the lastly, the most expensive water leak is caused by the infamous sunroof drains

There are 4 drain tubes in each corner of the big 3 part panoramic sunroof, and they can leak. Either because the drain tubes are clogged which is not a big surprise, but also because of the upper plastic endings of the drain tubes which simply get a little loose over time creating a gap around the connection, which allows the water to leak not just into, but also onto the drain hose. The front drain tubes allow the water to collect in the front footwell area and the rear drain tubes allow the water to drip in the spare tire area and most importantly, right onto the amplifier which is located on the right side of the trunk. The failed amp will cause issues with the MMI multimedia system, like no sound, random rebooting, it can drain the battery or the whole system will not work at all.

Keep in mind that all the MMI modules are connected with fiber optics so if one module is completely faulty, then the whole system will not work at all. If you don’t know which module is faulty then you can purchase a fiber optic loop bypass connector which will help you to find the faulty module. But remember, sometimes even two modules can be faulty at the same time, so in that case you have to buy more bypass loops.

If you don’t know which module is faulty, then you have to check all the modules by disconnecting each module and connecting the specific module cable to the bypass connector. So, for example, if your MMI is not working and you connect the amplifier cable to the bypass loop and the MMI starts working but without sound, then the amp is faulty.

And another funny thing, if you want to replace the amplifier for example with a new or used one, then you will have to bring it to the dealer to code it specifically to your car. But it’s also possible to repair it and in this case there is no need to code it since it’s the same amp.

But let’s go back to the loose drain connections and how to fix them. First you have to access them by removing some of the parts of the headliner. Then you can fix the connections freestyle basically, so you can put some glue into the gaps or cut off the faulty connection, heat up the drain tube and put the connection inside the drain tube. At the end any fix is better than no fix.

Also keep in mind, that various electronic gremlins can pop up at low battery voltage, and when putting in a new battery – you should do a recalibration of it via the diagnostic computer, since the battery management system acts differently to a new battery.

Suspension

This Q7 was available with the standard or with the adaptive air suspension.

The air suspension is fairly reliable. If something breaks on it, then it’s usually the air compressor or one of the height sensors + it’s good to check the height sensor link rods because they can be sometimes seized up. There are also cases of sticking residual pressure valves causing that one side of the car will be higher or lower (this valve is on top of each air strut). On the other side, there are not many cases of leaking air struts yet, but they will obviously start to leak sooner or later mainly because of the age, not because of high mileage. So on cars which are older than 10 years I would be definitely prepared to replace them.

Most of the suspension parts (control arms, bushings) are durable, but coming to 200 000 km some of them can be worn out. But things which will be definitely worn out much earlier, are the tires and brakes.

Besides the regular steel brakes, some of the versions were available with the Carbon-ceramic brakes too. They obviously last a lot longer than the regular steel brakes, but they are really, really expensive, so it’s good to avoid these car with ceramic brakes mainly if they have more than 130 000 or 150 000 km, unless you have the money to replace them or they were replaced recently.

Petrol engines

All the petrol engines are equipped with direct injection, so the well known problems with carbon build up or injectors can occur. Ignition coils can fail as well, but this is nothing new and you can obviously minimize the possibility of these issues. (possible carbon build up after 200 000 km, mostly 4.2 fsi and 3.6 fsi)

Then mainly the 3.6 l and the 4.2 l engines can have faulty camshaft adjustment solenoids. Usually, they get stuck because of long oil change intervals and in this case you get fault codes for the camshaft position, misfires or fluctating/bouncing idle. The 6 cylinder engines have two of them and the 4.2 l V8 has 4 of these solenoids, but interestingly replacing them is much easier in the V8 engine than in the 3.6 l motor. Sometimes you can get slight oil leak from them as well, but in this case there is no need to replace them completely, you just need to change the small o ring on them.

The 3.6 l, 6 cylinder engine is not bad, but in cars made to 2007 it can have issues with the oil pump bolt. So basically, the oil pump sprocket bolt can break or it just become loose over time causing loose sprocket, loose timing chain and in the worst case a destroyed engine. This is not extremely common, but it can sometimes happen on low mileage as well as on high mileage cars. They say that the bolt they used is not strong enough + it was not torqued properly from the factory on some cars. Interestingly, cars made from 2008 do have updated, stronger oil pump bolt so they won’t have this issue. All in all, if you want to preventively change this bolt on cars made to 2007 then you can, but you have to remove the engine to access it.

Then there is the 4.2 l V8 which can have some problems too.

-First of all, this engine has two high pressure fuel pumps. The good thing is, that they are located on the top of the engine so replacing them is pretty easy and they usually don’t fail completely. However, the bad thing is, that over time fuel can slowly leak right out of the solenoid valve of this fuel pump. Which is definitely not good, to say at least. Now, you can’t buy just the solenoid unit itself as a spare part, so you have to buy the complete pump. And if one of the pumps starts to leak, then don’t worry, because the other will sooner or later leak as well, so you should definitely occasionally check them-they can start to leak even after 140 000 km.

-The next problem can be with the intake manifold actuator arms which can become loose over time and they can pop out. In this case there is no need to buy some new expensive parts, just buy some tiny metal e-clips and put them into the grooves which are on the end of these arms. Interestingly the grooves are there from the factory but they don’t offer any kind of genuine e-clips to put them there. Rarely the actuator flaps in the intake manifold get stuck or the actuator motor itself can have excessive play in it and it can throw fault codes, but these are not extremely common problems.

After 200 000 km you should be prepared to change the timing chain and the plastic guides, but I will come back to this topic a little later.

The last thing is, that you should check the coolant while the engine is still cold. It has to be clean, topped up and you shouldn’t see any oil in it, if there is oil in the coolant then just run away. You can check it visually or smell the coolant for oil.

The 3.0l TFSI supercharged engine doesn’t have any major problems, just the usual stuff.

Diesel engines

-The 3.0l V6 is a very popular engine, but it has these variable intake manifold flaps which can sometimes fail. In this case you get only a check engine light, so the car will drive fine. The flaps can be stuck, loose or the actuator motor can be faulty. The whole intake manifold part is obviously expensive but you can find repair kits for a much reasonable price.

-Then there are cases of popped out fuel injectors because of the snapped bolt on the injector, again on the 3.0 l engines. So, it’s good to occasionally check these bolts or preventively replace them if you want mainly on cars made from 2009 or 2011 which have more than 100 000 km.

When it comes to injectors – they can be faulty on all the diesel engines, but usually just after 200 000 km. In this case you can most of the time notice a couple of signs like the occasional light grey smoke from the exhaust while acceleration, or at idle and also a slightly bouncing idle when the engine is warmed up.

The reliability of the 4.2l V8 is very good if it’s maintained properly and used mainly on longer journeys of course. It has 2 turbochargers which are usually ok unless the previous owner abused the car. So if you want enough power to overtake most cars on the road but you still want a reasonable fuel consumption then choose this engine.

And if you want something special, impressive and insane at the same time then choose the 6.0 l V12. The reliability of this V12 is basically the same as the reliability of the 4.2 l V8. Just keep in mind that, the V12 has 12 injectors, 2 high pressure fuel pumps and there is a bigger chance that the previous owner abused it, that’s all.

All of the engines are equipped with timing chains. The tensioner and the plastic guides can be worn + the chain can be stretched, but again just after 200 000 km. Now, in this case you get the well known short rattle at cold start. The funny thing is, that there aren’t many catastrophic engine failures because of the timing chains, I’m not saying that there aren’t any at all because they are, but they really are not that common. I mean you can let the engine rattle its own path thru life, because why not. And actually, a good amount of owners are testing the chains lifetime this way. You know, it can rattle a month and then the chain can jump a teeth or rarely you end up with a destroyed engine, but it can also rattle for a couple of years without other problems. At the end of the day it’s up to you, if you want to push your luck or not. The timing chains are located on the back side of the engine so you have to remove the engine to change them.

Transmissions

This Q7 can be equipped with the older 6 speed or the newer 8 speed automatic gearbox, and the 3.6 l petrol engine was available with a 6 speed manual as well.

The automatic transmissions are usually ok, just check them before buying. They should change gears smoothly without slipping, hesitation or fluctating revs. + after 200 000 – 250 000 km you should be prepared to replace the torque converter mainly if the previous owner never changed the oil in the gearbox or the car was used a lot for towing (bad torque converter – fluctating RPM, slipping, hesitation).

It’s also important to check the fluid level in the differentials and change it regularly. If you don’t, then the low differential fluid will kill the differentials over time.

And lastly, don’t forget to check the car properly for little rust bubbles mainly on the tailgate and around the door handles. I’m not saying that this car is notorious for rust because it’s not, but still, it’s better to check these areas more closely.

To summarize things up: buy only a car with a proper maintenance history, find a good independent specialist, change all the fluids in time and keep at least 3 000 € for the possible repairs, and if you are buying a car with more than 200 000 km then you should keep twice as much money. And if you have personal experience with this car or more information about it, then you can write it into comments!

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