2001 Q45T using coolant help!! Any Ideas?

[q45roadwarrior]

Ok, I know i must provide enough info so that someone can make an educatedguess as to what is causing this very slow loss of coolant.

Purchased @ 38,000 mi. not much history prior to that (oil changes done elsewhere) 30k service done at dealer prior to purchase. Oil changes must have been done often (IMO) due to the inside of the engine (as you look down thru the oil filler cap) it was clean as a whistle. Since purchased 12/02 :Mobile One every 3,000 miles,-- trans flush with Mobile one immediately after purchase, then every 20k (twice since purchased) --Coolant flush at purchase,then again every 20k (Twice since purchased) with Infiniti coolant. Brake flush at time of purchase (With synthetic), Synthetic diff fluid changed every 20k -syn power steering changed every 20k................OK, so back to the coolant leak. I thought it was losing coolant, an had a dealer check it. They say they ran a pressure test an everything looked ok.. The car has never overheatedbut I think think the temp gauge is ever so slightly to the right (hotter) than its always been. No leaks that I have seen and the time needed to lose the coolant fluid in the bottle is about 3 to 4 months and 3-4 thousand miles.

Current mileage:87,000 This is making me wonder if the leak is internal. no water ccoming from anywhere I can see.

[qship96]

get a oil analysis done,that will tell you if the coolant is leaking internally,for external leaks,look for white stains around all connections and cap.

[911/Q45]

Exhaust sniffer can tell if it's going out that way.

[DAEDALUS]

There's also exhaust dye detectors for the coolant. Never had to use it yet but it's cheap, bought it just in case. I'd do what qship recommended--trace the coolant path and look for white crusty deposits where the rubber meets the metal. Check the obvious places, radiator hoses, underside of water pump, plus don't forget the hoses in the valley of the engine and around the throttle body. Hopefully you don't have a tiny leak at the heater core (any moisture on passenger-side floor?) Such a small leak wouldn't show up on a 10-minute pressure test.

[Q451990]

Nice to see another fellow South Carolinian here. I was born in Spartanburg and went to school in Roebuck.

I'd check again to see if you can find any white crusty trails around the coolant hoses, down under the intake, near the water pump etc. I seriously doubt that you have a bad head gasket (burning it) but I guess that's always a possibility. If you think it's running warmer than usual, a new thermostat is cheap and probably something you'll want to do as preventive maintence anyway...

It sounds like your Q has been very well maintained... what dealership are you using? The maintenence you mentioned seems well beyond the usual dealer suggestions.

Heath

[q45roadwarrior]

Thanks everybody for the suggestions! Luckily, I still have 14k mi. left on my Certified extended warranty, so I hope this is covered.

Hey there Heath! I have been reading posts from you, PalmerWMD, and Q45 Tech since the old days @ the yahoo board. You guys are really knowledgeable'(and I especially appreciate PalmerWMD's post about being nice to each other, as I almost have stopped visiting because of the "One Upmanship" attitude of a few posters.)

I use two dealers: Greenville, SCSteve Duncan is my service guy.......and Charlotte, NC.

The Charlotte store does far more business,(therefore sees more Q45's) thanGreenville. I use Charlotte for the things that I cannot figure out, and Greenvillefor fluid changes,etc.--No offence to the guys in Greenville, I have found that any shop that sees more of the same cars, will better be able to diagnose a problem.