Running Cold - Weird Smell - Thermostat?

[Eggman]

Happy Holidays to all at 318ti

Driving home for the holidays, noticed near the end of the trip the temperature gauge was creeping down - running cold, not hot. Near the blue.

There was no smell, no smoke, no other lights, no performance issues (other than heat seemed to stop working so well too) and we were about 30 miles home. Since the engine was running cold, not hot, we decided to keep rolling.

A couple of miles from destination we noticed a very faint smell, (my girlfriend was not even convinced it was there and she's more sensitive to this then I am) of what seemed like "fireplace" smell. Only way I can describe it. We made it with no other issues, and indeed after pulling in I popped the hood and the smell seemed a bit stronger, though still not overpowering.

Well now I am 500 miles away from my regular mechanic who is also out of the country until after the 1st. Need to get back home. Any advice on where to point the local guy? Honest mechanic we have known for decades, just not sure how many 318ti's he has worked on.

Stuck thermostat? Coolant Leak? Is it possible to damage the engine by running cold? Thanks so much.

[MPWR]

Originally Posted by Eggman

Stuck thermostat? Coolant Leak? Is it possible to damage the engine by running cold?

Yes, running the engine too cold is not good. It dramatically increases wear.

Most likely the thermostat is stuck open. It is a really easy DIY fix on an M44.

The other possibility is that there isn't enough coolant in your system for the temp sensor to read. In this case it is possible for the temp to read low while the engine is actually overheating- not good.

Check your coolant level and bleed it. If lack of coolant isn't an issue, than it's likely the thermostat.

[Eggman]

ugh, OK. I'll check it out. thank you.

it does look to me like the coolant is a bit low (about 3/4 of the reservoir appears full), but the car is cold right now and I have never noticed where that level sits when cold.

mechanic is about 1.5 miles away. OK to drive there you think, or tow??? :-(

man i hope i didn't crack the block or something.

[Will'sBimmer]

There is a line on the side of the plastic housing where u put the antifreeze in. That is the cold mark (where the coolant level should be when the car is cold. If your antifreeze is not low then it is the Thermostat more than likely. It would be ok to drive but I would order another one and replace it.

[Eggman]

thanks. I think I am OK, I appear to be just barely below the line. but new thermostat is first on the agenda tomorrow. thanks, and will report back.

[tiFreak]

remember to bleed the coolant after you've changed the thermostat
http://www.318ti.org/forum/showthread.php?t=27983

[Eggman]

Originally Posted by tiFreak

remember to bleed the coolant after you've changed the thermostat
http://www.318ti.org/forum/showthread.php?t=27983

ok thanks, will do.

[Eggman]

So we replaced the thermostat, refilled the system, and all seems to be well, heat and temp seem good for now.

I told the tech - knowledgeable and honest guy - about the proper technique to bleed our cars and he said they use a pressurized/vacuum system to bleed the system so it shouldn't be necessary. Hmmm.... I did search and found some entertaining reaction to this in another thread but no one ever actually answered the question if that works for the TI...

Is he right? Should I re-bleed with the "incline" system anyway?

As noted above, I'm traveling for the holidays, so this is not my normal guy who does know these cars well.

Thanks for all the guidance and help folks!

[pdxmotorhead]

If its bled incorrectly it will overheat almost as soon as you start it.

If it will run for 5 minutes or so get up to normal temp and you see no issues then you should be good to go.

Recheck the coolant level OFTEN for the first week or two after this kind of work.

You might just open the bleeder screw to see if it burps any more air after a day or so...

Dave

[Eggman]

Originally Posted by pdxmotorhead

Recheck the coolant level OFTEN for the first week or two after this kind of work.

You might just open the bleeder screw to see if it burps any more air after a day or so...

Dave

cool, thanks will do. I am assuming if have to "top off" that I should open the bleeder screw for a few minutes too.

[pdxmotorhead]

I usually do a mini bleed at each oil change, I start the car after teh oil change and while I'm there I crack open the bleeder just a tic to see if any air comes out.

Unlike most I've been lucky, I've drained the cooling system multiple time and never had a issue, but I run Water Wetter and it definitely helps get air out because it breaks surface tension and the bubbles don't form in the system as well. My driveway also has just a hint of slope to it ot the rear maybe thats all it takes?

Dave