2kwik4u

2017 Q7 Prestige with 3.0T engine.

Have a coolant leak somewhere. It's at the local independent shop now getting diagnosed. If he can't fix it today I've asked that he leave it together so I can make a trip this weekend to MO. It's been leaking for awhile at a relative slow rate (20oz bottle of water a week or so). I'm pretty confident it can make the trip without an issue with the leak, and he can fix it later if it's a big deal. Of course the fix is best here, but I'm developing my contingency plans just in case.

So far, the low coolant light has appeared 3 times, and each time it's been during initial startup in the morning. I was able to shut down the engine before it was hot and add some distilled water to keep me going until I could get into the shop. IF.....that's a big if....I get the low coolant light while driving and the engine is hot, can I open the reservoir and add water or do I risk injury with a pressurized system? My Sierra I could open the reservoir at any time regardless of heat because the reservoir wasn't pressurized. My TBSS on the other hand had a pressurized reservoir so I couldn't open it at temp (tried once and am lucky to not have permanent scars from that).

Anyone know how the Q7 system works? Can I open and add when hot, or do I have to wait for a full cooldown to add?

mhoran89

the coolant expansion (overflow) reservoir should not be under pressure ever. on the other hand I would put a towel over the lid while opening it for the first time if the car was hot (just in case). a rubber glove might not be a bad idea either. I am sure someone else will chime in though...

2kwik4u

Thanks.

That is what I thought, however I saw the latch on it, the exclamation point label, and the O-Ring on the cap. Thought it was worth an ask before I did it. I'll definitely have a towel or other deflection aid over it when opening for the first time for certain.

I've had scalding hot coolant to the face and body before. It's far from pleasant.

2kwik4u

Mechanic kept the car overnight. Said he can see evidence on the water pump of leakage, but can't find any coolant actively leaking out. Was going to let it cool overnight and do a pressure test this morning to try and nail down the leak. We'll see what shakes out.

Supposed to drive it on a 4.5hr road trip tonight. Fingers crossed it's fixed today. If not, it'll just leak for the trip and I'll keep an eye on the level along the way.

GDawgA4

It commonly leaks out of the weep hole by the pulley so it's not an "active" leak per say but it gets worse. Mine had been slowly leaking for some time until it was more constant. I noticed coolant was being sprayed up around the engine cover from it dripping onto the belt and getting slung and the coolant level finally got low enough to trigger the warning light.



https://www.audiworld.com/forums/q7-...-pump-3027510/

2kwik4u

Thanks for the insight. We think it's the water pump. He was describing the same "slung coolant" look all over the front of the engine. I'm guessing that's what's failed here as well.

I saw your "how-To" and it's something I could tackle in the garage, I just don't have the bandwidth to get it done. Career is taking off, I'm working on my MBA, and have an 11yr old and 4yr old in soccer at home. Time isn't something I have a lot of to spare, just gonna pay to have it done. He's guessing around $700 for the repair, and best I can tell you had about $275in parts. Seems fair for someone else to bork with it instead of me.

GDawgA4

I get it. I had to find an open day without kid activities so I could spend an afternoon on replacing it. What he's charging definitely seems fair if it's $700 including the parts.

2kwik4u

$700 includes parts, and labor to replace the water pump, a couple hoses, and refill with new coolant. It also includes the time he has in it for diagnosis of the problem.

If anyone is around the Louisville, KY area I highly recommend Jeff at Autowerkstat. Clearly some others around here like him as well. Had a nice TTRS on the lift, and an S7 ready to come in as well. My beat up Q7 looked a little out of place

Handydoctor

It's of course under pressure. Most cars, q7 included, don't have the old school reservoir anymore and no radiator cap. It's one piece and pressurized everywhere.

richsurf

Sounds like you got a good deal on the repair.
As I always recommend, report the failure to the NHTSA. There are just too many bad water pumps out there.