So up here in North Dakota it's hovering around the -25 mark w/o windchill (~-50 with). I figured it would be a good idea to let the car warm up today to be safe. It barely turned over and when it did there was a distinct smell of raw gas, which has happened before when it's very cold out. It is also idling very rough though, with an odd noise coming from what sounds like the serpentine belt... Here is a video:



As for the leaking injectors, I've heard the o-ring around them is not meant to withstand much below -10 degrees... Is there any fix/replacement for this?? I have no idea about the noise, though.

Any help would be greatly appreciated, thank you!

 

No idea on your noise.

I smell raw gas when my 30V V6 is cold too. That's what the the secondary air pump is supposed to help eliminate. But at some point the exhaust is just to cold to burn it off, even with the secondary air.

I live in the same climate you do. Was -21 when I started mine this AM. I've never had a problem with the injector O rings, and I've driven Audi V6's in this weather for about 20 years now.

 

What's that line on your serpentine belt? Has it always been there?

Does the noise go away when you rev it up a little?

It's one of your pulleys obviously, but and I'm going to stab at the dark in here and say it may be the serpentine belt tensioner causing the noise.....it sounds like a plastic/rubber wheel turning that lost all it's grease (frozen)...hope that makes sense.....like plastic/rubber scraping because it's frozen.....mine did that years ago, but it went away and I never investigated it further. But if your belt isn't tight due to the tensioner and/or cold, your car will idle rough...just a guess though...

The Air pump can't handle the cold, so you smell that smell....

I'm in IA, but you both have it worse....

 

Yes, it does go away whenever I rev it to around ~1k.... Is it something to worry about?

 

Yes. Getting stranded at -25 is something to worry about.

Sure sounds like something on the front...either serp belt or timing belt related.

 

I never drove mine when it did it. And I would suggest you do not drive it either.

If you have an antifreeze mixture of 70% Glycol and 30% water, it WILL start to freeze at -35 degrees F. So, now, if you have a 50/50 mix....it will start to freeze at around -20 to -25 or so....wikipedia.....

I put all 3 of my audi's in my garage 2 days ago and haven't moved them....I'm attached to them....

My 2013 GMC work van wouldn't start this morning and when it did, it made god awful noises-I let it run for 45 minutes, then went to work...and prayed nothing would happen....

I'm again guessing it's your tensioner that is frozen and not flexing correctly, it's a BIG guess. When it warms up tomorrow or next day, start it up, let it run, warm up and chances are the noise will be gone, if not, it'll be warmer to investigate.

the line on your Serpentine belt, has it always been there? Because it looks like something is making a mark on it, which isn't good, and if you haven't seen it before....that's probably the part where the noise is coming from causing that line.....

 

Hopefully when it warms up it will be gone - I let it warm up for about half an hour and the noise was quieter, and then drove around the neighborhood for about 20 minutes to get everything circulating - it runs, shifts, and feels fine otherwise once it's been running for awhile. No CEL's or lights of any kind except for a warning about the secondary air pump (which is why I'm assuming there is the smell of gas on cold start).

When I got home, it was idling fine with good oil temp. and an engine temp of ~200-215 degrees. The sound was gone and when I shut it down and restarted after a couple minutes it fire like it was a summer day.

I don't remember whether or not the line was there previously (not helping my case, I know...).

Hopefully tomorrow will be better, temp wise. This cold weather just wreaks havoc on cars and I unfortunately am forced to store it outside...

Thank you again for the help and I will update tomorrow with any news.

 

Good to hear.

Hoped it would go away for you as mine did, but you never know. All cars seem to make noises in sub zero temps...and worse when it's extreme like we have lately.....just don't drive them until they warm up for 20+ minutes...

When you look at the belt, look at the serpentine belt a little down further toward the other pulleys and you'll see the 'other' side of the belt (the side without the line)...see if it has cracks in it.....and then since that line shouldn't be there...something is rubbing on your belt and causing that 'groove', which in turn weakens the life of the belt....so follow the belt around the best you can, and you may find where the mark is coming from....

 

I didn't read through everything, but heres my take-

Cold makes weird stuff happen to cars. There will always be extra noises and vibrations that are seemingly unexplainable. If they go away when the mercury goes above freezing, I forget about it.

 

so ignore the issues until May?