chago996

'01 996 with 96k. I had the coolant tank topped off 2 weeks ago and today I noticed it was under the min. level again. No leaks anywhere that I can tell and the car runs perfect. Coolant tank replaced by P. dealer 1 year ago. Any cues as to what's going on? Thanks

ivangene

Aliens -

check the oil dip stick and fill tube.....any creamy coffee color there?

1999Porsche911

If you haven't driven the car much since the coolant tank was replaced, you could just be getting low because there is air in the system that is slowly bleeding out. This is normal on an improperly filled cooling system and will work itself out over time. Keep an I on the level in the tank and fill as necessary untill the level becomes stable.

ElTorrente

Yeah, probably just air bubbles working their way through the system.

C4CRNA

Any water/white smoke out of the exhaust ?

chago996

No white smoke, no creamy colored oil on dipstick, tank and cap replaced by dealer 1 yr ago. Dealer topped of 2 weeks ago during 90k check-up with no issues. Just low again

cdodkin

Make sure the cap goes on square - they can easily cross-thread and leak.

STRSHP

also check the back of the tank. If it is gone again, typically it leaks where you cannot see it. Mine was cracked and until it was removed, it was impossible to see

chago996

Wouldn't there be a noticeable leak on the floor. That's how I noticed the original tank was cracked 1 yr. ago. Now, there's no puddle or wetness anywhere. cap seems secure

redridge

if your cap ends on 00... you should get an updated cap.

Dave!

I'd bet on bubbles in the lines, when I had a bad cap it was peeing coolant when I parked it hot.

uberskier

+1 on the cap.

I didn't do enough research before I took it into the dealership. Same signs as you, couldn't see a leak anywhere, but level kept dropping. Dealership checked everything and replaced the cap.

chago996

Cap # ends in 01. Is there an updated version? Shouldn't updated cap come with new expansion tank replaced by dealer 1 ur ago?

yasuro

the cap is ~$12. go ahead and order one from suncoast or sunset. they can send the latest version/revision of the cap.

Ryan C

Usually when you fill the expansion tank to the full line and then get the car hot, some of the water will come out and kind of find it's operating level. I don't usually see it go below the min. line but more often than not I find that they level out closer to the min. than the max. It is a good idea to change or at least check the cap anyway, but you may find that this is just how it is. Unless of course you continue to lose water but you didn't mention puddles.