More temp and coolant problems

O.K., now i have changed the reservoir tank and cap with the latest part numbers only a month ago and the needle never quite went back to between the 8 and the 0. just a little bit more toward the 0. Yesterday, the needle went just a hair past the 0 and back again. then the light started to flash (slowly I would say). Turned off car. let cool 5 minutes. tail fan was on! so there is no malfunction with it. Checked coolant level and it seemed a little low ( i was actually able to add some fluid). This is my question: What else could possibly be leading to a coolant loss? I changed the cap and tank already? The front radiatiors are clear of debris ( but I do want to check behind them, the tire side, for more crap). The fan is turning on, but that is because the system is detecting higher than normal temps. Could it possibly be that the new tank is also cracked. I dont even track the car or short shift of abuse it all. I do drive spiritedly, but I dont abuse. HELP!!! Thanx, Peter

maybe some air in the system...has it been burped?

If you don't find anything you might run an oil analysis to look for traces of antifreeze in the oil.

Peter, make sure all the air is out of the system. The easiest way to do it is to leave the valve on the cap in the open position for about 200 miles...

Air is probably in the system, but that's not going to affect the engine temp unless you are REALLY REALLY low. Your problem is as follows: I had a 99 C2 and had similar problems with cooling. Most if not all of the early 996's had some cooling problems if they were first generations ie ones with the old egg style lamps before the restyle to make them look like the Turbos. I think it was 1998-2000. If you notice that the 2001's have a more "scooped" front air intake than the 98's, 99's, and 2000's. That's b/c they couldn't suck in enough cool air.

According to your post, you do not have a temperature problem at all, just a problem with the indicator light. Most probably air in the system. As mentioned above, drive the car for awhile with the bleeder valve open and that should remove all the air. Then fill to tank to it's proper level and you shouldn't have anymore problems. The engine fan is turning on because the light is flashing and not because of temperature.

Exactly which part is the bleeder valve? Is it the black fluted round mounted piece located on the top of the expansion tank near the blue fill cap that has the metal handle/loop on it? Do you mean that I should lift the metal part up so that the plastic valve piece attached moves. It is currently in the laying down position. Should it be in the vertical-most position? Is that the position that opens the valve? If i leave it open to burp the air, how come air cant come back in? Assuming I do have air in the system. (after all my mechanic recently replaced the expansion tank but did not flush the system, he only added the required amount of coolant back in. maybe he didn't burp the system) why is it i still smell the sweet smell of antifreeze. And you know, I actually detect the smell once the needle starts to go beyond the 8 and 0 split position. If I let the car cool down and then drive again, no smell and good needle positioning, but once it starts to move, and touch the 0, I actually smell antifreeze. Are there any hoses that are problematic as well. I know my mechanic checked and said they were all good. But maybe one of them is now bad.

OOPS, sorry, forgot to say thanx for the input so far. I would be dumbstruck if the problem really is as simple as you experts point out so far. Thanx, Peter

Did you put 50% distill water and 50% coolant when you drain and filled the coolant? You may have a leak somewhere. A pressure test can confirm whether this is true. Your temp is higher than normal. Where do you live? You may want to use a 70/30 mix (70% water) if you live somewhere hot or tend to sit in traffic. Check your engine oil level too as engine oil helps to cool engine as well. If oil is low, have it topped off.

I live in California, Los Angeles and i do sit in traffic. The coolant wasnt flushed. just topped off after the expansion tank replacement. the oil level is good via the dip stick. The electronic gauge is all over the place. The other day it actually flashed the bottom bar, but upon physical dipstick measurement it was perfect. I dont understand why. Today with the temp needle higher than normal, my oil gauge (electronic) showed it was full (one bar below the highest). Still want to know if the bleeder valve is the one connected to the round black piece! Thanx, Peter

Your temperature is NOT above normal for city driving in warmer weather. You will regularly see 215 - 220F and higher on the 3.4 and less on the 3.6. Yes, what you described is the bleeder valve. Ckeck for pressure leak by removing the coolant tank cap after the car has sit 4 - 5 hours after running. If you don't hear pressure being released, you have a problem.

I want to agree so as to not overthink about it and lose sleep. But, the gauge NEVER played around before. It was stuck b/w the 8 and 0. always!! and I do smell some antifreeze. Again, please let me know if the bleeder valve is the metal loop on top of the round black piece located on the top of the expansion tank. I have a good drive home tonight and would like to open this valve up. Thanx for all info guys, Peter

I edited my previous message to include more. What year is your car?

Sorry, I am just overly anxious about my red baby and cant stand to see it ill. Want to administer therapy NOW and enjoy her soon. OK. so i will lift up the metal loop so that it is in the vertical-most position causing the valve to be in the open position, to allow the system to BURP. Then I will check the pressure as you described after the car has sat and cooled for 4-5 hours. Maybe more, just for the hell of it. If hissing sound and lower temp readings, I will be forever grateful, and my mechanic disappointed!!! I am curious of course how much hissing/pressure should there be after 4-5 hours. Should the engine be completely cooled down when opening cap or still hot and some hissing / pressure release. Thanx all, I will keep you posted once i perform this procedure. Peter

It is 1999 MY c2

You won't hear any hissing if the bleeder valve is open. Shut it about 10 minutes before parking to build up pressure. ANY hint of pressure being released after a few hours indicates the system has no leaks. You have my car.

You mean 10 minutes before completeing my drive, pull over, close the valve and then complete my drive? Or after I park, close the valve, then a few hours later, test for pressure? I want to make sure i am going to do it right. I am home now, car is parked, valve is still open (drove home with it open). Needle went as far as the right side line of the 0. But no higher. Please let me know. Thanx, Peter

You mean 10 minutes before completeing my drive, pull over, close the valve and then complete my drive? YES. What was the air temp on your drive home and how long a drive was it?

RE oil level, be sure to measure that when car is flat and 10min after engine is shut off. My electronic sensor tends to fluctuate a little each time I measure it (by 1-2 bars) but never gave warnings.

The air temp was mid 90's and muggy. stop and go traffic. drive was 25 minutes or so. djantlive: thats exactly the way i check the oil. I really dont even both with the electronic gauge any more, it is too varied. I trust the old fashion method. check the dipstick. I had already parked the car and let sit for a while without closing the valve again. I was wondering what about letting the car rest for some hours, then drive again with the valve open, stop to close the valve, drive again, then park and check for hissing. I am assuming I am only going to barely undo the cap and test for pressure and not open up completely because the engine is too hot! RIGHT? Hell, i dont want to get burned!!! thanx, Peter

Just go out now and close the valve and start the car and run it for ten minutes. Then check the cap in a couple of hours.

OK, will do!! thanx, Peter

Well, it has been five hours since I turned off the engine and when I went to open the expansion tank cap there was in fact some hissing, not a lot, but there was some pressure release. I suspect that if i had attempted to open the cap at the 2 or 3 hour mark instead of 5 hours, then there would be a marked increase in pressure. I am going to drive the car again, get it up to temp, park, ensure valve is closed and test again in 2 or 3 hours this time and check for pressure amount. I am hopeful at this point that I dont have leak. Any feedback? thanx, Peter

Sounds like the system is air tight to me. Should have no leaks and cap is sealing tightly. Now go out and enjoy your ride.

Just to get in on this thread. I noticed after I did some maintenance that my coolant was low. I added a quart that I had lying around. I cannot say whether there was a leak or not or jsut that I never burped/bled it to get the right overflow amount. However for the hell of it I opened up the bleeder and drove around. I found that it took about 2x as long for the car to get to temp as when closed. I also noticed that the car seeminlgy was running cooler, albeit exteraneous outside temperatures could cause that. IN any event I closed the valve again and the temp seems to be a bit higher than before? Again it has been hotter and the driving style will definitely acount for that. My main question is whether it is normal for the car to take 2x as long to get to temp with the valve open?????

Yes, a pressurized liquid will heat up faster. without pressure in the system, the coolant would boil away eventually.

interesting so is it bad to drive around with the bleeder open? When is it bled, other than looking at the coolant level and noting no further loss?

I am actually starting to wonder whether or not the bleeder valve was left open at some point in time and it resulted in a loss of coolant. I know i was messing with the metal loop recently, especially since the expansion tank was just changed but now I am really not sure. I just instinctively made sure that the loop was laying down flat for reason number one it didnt seem right for it to stick up above the rim of the engine compartment rim and number two, it seemed like the prefered resting position as opposed to it being locked into place in the vertical. I am going to go for a drive now, What can I say, it is a tough job - but one must do it. I will check for temp issues and coolant levels. will post again afterwards

Yes, keeping the bleeder open all the time is fine. That's how cup cars run all the time.

Yesterday I drove the car with the bleeder valve open and did some serious spirited driving. The flow of traffic was on my side for once. Anyways, the needle only moved up to the "splitting the 0" position. I drove high speed, low speed, a/c on and off, just to vary the conditions to test the gauge. today, I removed the expansion tank cap and started the engine and let her get up to operating temp. Then let it cool down with the cap still off to allow any air to escape (a few hours worth). After letting it cool down, I topped off the coolant level to the point where the coolant was spilling out over the top of the opening. then closed her up again and went for a drive. Again as before, fast, slow, stop and go, a/c on and off. The needle went up only to the right side of the left line of the 0. So it is staying cooler than before. So the moral so far is that the temp gauge actually stayed at a lower level with the bleeder valve closed than open. But colder air temps today might have played a role in that. One other thing I did notice. recently my oil level gauge has been all over the place, but when I check with the dipstick it reads at the top/full dot/mark. Even when the bottom bar was flashing the day before yesterday, I checked the oil and it was ok. Today, the bar was flashing again. This was after my second drive with the bleeder valve closed. so I parked the car, waited 20 minutes for the oil to drip back and checked. Sure enough, the oil level for the first time in 7,000 miles of owning and driving the car, was at the middle mark, between the upper and lower dot markings. So I added a full quart of 0W40 and checked again. It registered at the top mark. but because I didnt start the car and get it back to operating temps and then cool back down for 20 minutes or so I dont know if the reading is accurate. I will however check tomorrow after driving the car. I hope I didnt overfill, as my intention wasnt really to add the whole quart, it just sort of happened. You guys think that a drop in the oil level will play with the temp readings. Seems like an obvious answer but still want to hear from the experts. Thanx everyone. Peter

Peter. Stop over analyzing. You won't enjoy your car. Remove the excess coolant from the tank so you don't find coolant dripping on the tailpipe. Your temperature is normal for your car. Depending on how hot it is,, the speed you are driving and whether the sun is out or not, your needle can be anywhere from between the 8 and 0 and to the right side of the 0 in 180. Your electronic oil gauge is accurate if you let the car sit overnight. Look at it before your start the car each morning and you will see the exact level of oil in the car. It can take an hour or longer for all the oil to fall to it's lowest level that will give you an accurate reading on the dipstick and/or electrontic gauge. Car MUST be level.

hello i have a 1999 911 , cooling problems also , temp gauge a little over normal after 20min of driving, in los angeles also, you sound well versed only had the car about 2mo. 68kmi. , mechanic didnt find coolant leak but it was low before I took it in , the cooling fan doest turn on except when I have the a/c on , then it runs normal on fwy or just above in city driving , any comments ? thanks

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If your temp gauge sits around the middle of the 0 on 180 uo to just a hair to the right of the 0, that is common for city driving in warm climates for the 3.4 engine and should not concern you. Your fans should be on at this time whether the air is on or not. You should never lose coolant. Possibly the previous owner had a problem and never properly topped off and bled the coolant system.

thanks , splitting the o and somtimes to the right of the 0 , glad you say normal , Im used to my Bmw 528 the temp gage pegged at middle and no fluctuation, - the front cooling fans do not turn on , only when I run the a/c , ..bad sensor ? easy to replace ?? appreciate youre input , also when cold at start up I hear a tapping or knocking sound , then goes away after 10sec, what do you think ,lifter sticking ? other than those two issues the car purrrs and runs nice I love that car! Thanks again

I don't know off hand the exact engine temp that starts the low speed fans for the radiators, but with your temperature that high, they should be running. Maybe relay (above your left foot in the well). However, there is a seperate relay for each fan, so that is unlikely. If it was both the fuses, the fans would not operate when the A/C was on. Be sure that the fan IS NOT running. Get out of the car and stick your ear close to either side of the front bumper. Slow speed operation can sometimes be very quiet. Disclaimer: This test will not work if your are deaf. The tapping is most likely lifters and is common and should not be a problem. Personally, I would not run the 0W40 oil that many do. Change to the Mobil SUV 5W50 or Castrol's Syntec 5w50 in cooler months and 15w50 in summer. This will reduce lifter noise and better protect your engine. You may also hear a loud blower noise from the engine compartment when starting the car cold. This is the air injection pump and will run for about 30 seconds so the exhaust warms up faster. This is normal.

Stop adding "coolent" start adding water. You live in LA and do NOT need coolent. Add some distilled water from now on. Also go to the dealer and flush the coolent and see if any faults pop up as well in your DME. Clearing some faults might fix the electronic oil issue.

Does anyone think that it is normal for the spoiler fan in the rear engine compartment lid to turn on even when the temp gauge is reading within the accepted operating range? Mine has starting to switch on occassionaly even with the temp gauge reading between the 8 and 0 of the 180. Interesting huh? any thoughts? Thanx in advance!!! Peter

The engine compartment fan is also controlled by the engine comaprtment temp. It will turn on when the temperature gets to about 180F. Most often in traffic on hot, sunny days or after turning the car off after a hard run in hot weather. The fan sucks air into the engine compartment to cool things down.

On my 1999 carrera I will listen close for the low speed fan , sincei its winter now I will leave the mobil 1 whatever grade is in there since I just had it changed , I will switch to the Mobil 5/50w next oil change , the temp I wont worry about unless it goes higher than 200f mark, do the newer carreras run the same , you would think they would fix the temp gage to accomodate "normal" and it does say in the owners manual going right on the temp gage is normal , just not used to seeing that, and on other cars it is a definite sign of serious problems. thanks for the input

On the 3.4, when your gauge is touching the right side of the zero, you are already past 200F and sitting at around 215F. Nothing to worry about in normal driving.

Thanks , nice car you have there, I was going to get a silver one , but I found this mettalic black with 18in wheels and better stereo, couldnt pass it up , do you have mods on yours and what do you reccomend , thx