hey guys.
i recently encountered a problem that never happened to me before. i have a 99 TL with 130K miles. Stock...

I turned on the AC and drove.. then i had to punch the gas a few times.. then i notice the inside near the pedals heating up, even when i had the AC blasting.. then i look at the gauges and my heat is raising up!!! it was like 3 bars away from TOpping out!!! I dont know what to do.. i immediately turned off the AC and the heat needle went down slowly.. what is going on? Please help!!!!

 

first check ur antifreez (is it burning, do you smell it, is there any smoke ??)then make sure ur fans are working
i had a 91 legend with 150k miles and it was doing the ( BLOWN HEAD GASKET! )

 

having the AC on should actually cool the engine because when its running both radiator fans are operating, when the ac is off only 1 radiator fan runs.

check the coolant level in the radiator, check the overflow tank for radiator fluid

 

you mean overflow tank for coolant right, radiator fluid and coolant are the same. I had a related question, i put in prestone advanced coolant 50/50 a while back. I have not experienced any temp spikes or coolant level changes, but when I hit WOT sometimes I smell a faint gas smell, maybe its other cars, but I get paranoid when I smell that, it's like not completely burnt fuel, not raw gas from the pump, but I still smell it. i will check my oil tomorrow and smell for gas, but i doubt that's it because my car is running fine. any suggestions on checks and balances?

 

Yep.

Also, are you running the original water pump? It might be going out.

 

Thermostat?

 

If it's related to your a/c maybe the compressor's seizing up?

 

yes the overflow tank, and yes they aer the same, i was having him check to see if there was coolant (radiator fluid) in both and up to the correct levals.

you shouldnt smell gas from your car period. unless you have a leak there isnt much you could check for.


still shouldnt cause it to overheat. if it was seizing up, you would be hearing the belt squeel, smell the belt burning or hearing the compressor makng noises, loss of ac, but it wouldnt cause the car to over heat.
the other possibility like hardrock32tls stated would be the thermostat, and thats a lil more difficult to inspect

 

Start with the fluid checks of course... if all else fails, then you can look at the thermostat. The thermostat not opening at the correct temp will cause this problem, it may have just been great timing that just after the A/C was turned off, that the thermostat reached the point that it opened and started cooling off the engine.

DenverTL... just a safety reminder, PLEASE do not open the radiator cap with the engine hot, and you should not ever have to open the cap (except to do a change of fluid), fill the coolant through the reservoir. Modern Radiator systems are what is call closed systems, and the reservoir will hold extra coolant when it gets hot, or supply coolant when it is needed by the engine (when needed, the system creates a vacuum and draws more fluid in), just make sure that it is to the full line, about ¾ of the way up the reservoir bottle.

 

Check all your fluids, thermostat, etc, but whatever you do, DONT DRIVE if its OVERHEATING. Sorry for shouting, buts its very important. These cars have aluminum heads, and can warp em, and blow the headgasket in a seconds if the car overheats. If it does, pull over immediately, crank up the heat, and open the hood.

Its odd, but turning on the A/C shoudl cool down the engine due to the extra fan. Not sure why yours is causing it to heat up more. Either way, if you use yoru A/C again, and notice the temp guage creeping up again, turn it off right away, and leave it off until you have it looked it. Good Luck

 

hey guys.. thanks for responding.!! well so far.. it hasnt been overheating.. but whenever i have the AC on and i punch the accelerator a lil.. itll start to get hot.. but if i dont punch it while having the AC on.. it is normal and everything is cool.. so I think the only problem is when i punch it with the AC.. maybe the engine is working to hard or something??

 

Well it does not sound like something is right and I would think that you would need to get it taken care of as soon as possible. fsttyms1 being the resident machanical marval may have a better idea of what it is. Maybe the compressor is loading down the belt system and slowing down the waterpump? That is just a theory mind you.

 

When you punch it with the AC on, The AC compressor kicks off and your ducts will blow hot air, almost 90% of cars do this to give you the most performance when you punch the gas to the floor. If the AC didn't kick off, that would be a problem. I beleive it shuts off the compressor at ~90% throttle. The overheating part could be anything, fan switch, bad Radiator cap, water pump, thermostat stuck shut.

 

the ac compressor has a wide open switch, when the throttle is wide open the ac compressor should shut off. if its not the relay or something else may be bad.

there should be no reason the temp goes up under WOT with the ac on that i can think of. it doesnt make sense. the ac is just a belt driven part of the car like the alternator.

Unless its the Engine coolant high temp switch.
to prevent the possibility of overheating some (not sure if teh tl has it or not) vehicles are equiped with a coolant temp switch that dissengauges the compressor clutch when the coolant temp exceedes a predetermined level,

in any rate id bring it in and have it checked out. the last thing you want is the car to over heat, even a fraction of a bit could be very costly (like time for new engine)

 

If your car is overheating...do not turn on the AC...just like when you go up a steep mountain pass...they have signs to turn off AC to prevent overheating. Turning on AC actually makes the engine work harder...irregardless of the AC fan going. Turning up the heat full blast would help. Trust me...i had to do this several times on my old car. But most likely your thermostat needs to be changed. or something is wrong with your water pump.

 

actually the amount that AC actually makes the engine work harder is negligible, and turning on the AC does help, having both fans running will cool the engine. turning on the heat also works due to drawing heat thru the heater core and having the vent fan move air across it. But regaurdless, the car shouldnt be overheating. my car will idle all day and the temp gauge will never move. something is wrong (probably the thermostat)

 

I'm guessing either the t-stat or the water pump.

When was the last time you flushed the radiator and replaced the coolant?



My friend used to work at a Jiffy Lube and this Grand Am came in with an overheating problem (who the hell takes their car to an oil change place for an overheating problem?).

The t-state was replaced, but it overheated again. Finally, he asked the owner when the last time coolant was replaced and with over 100k miles on the clock, the owner said never.

The coolant had turned so acidic that it ate through the water pump blades and the coolant wasn't being circulated.


I thought it was funny for some reason.

 

my coolant is 185,500 old

 

 

still good to below -40

 

The only time my car ever overheated was when I hit that freakin' giant raccoon going 80 mph. The radiator got bent in half and the support snapped in 2 places. Of course, the coolant leaked out. Since it was during the winter, I figured the wind should keep it cool enough to drive for a while. Nope... I couldn't even go half a mile before the needle almost went to the redline... brrr... that was a scary moment. The fucker was rising as fast as the tachometer needle!!

 

i wish we had the cyl deactivation like the northstars have. my dad hit a deer with his aurora years back out in the country and had to drive teh car about 50 miles just to get to where his cell phone would work with no radiator fluid. got it fixed and 200k later the engine was still running strong. (guess GM wasnt crapping when they said you could drive teh car with out coolant)

 

Wasn't that without oil?? Or was it both?

I seem to remember reading a test a long time ago where they drained all the oil out of a previous generation STS and drove around a track.

 

no that was engine coolant. the car would shut down 4 cyl and run on the other 4 and the pumping action of ari being run thru the engine with out gas and spark actually cooled it. when the 4 running cyl got too hot it would activate the 4 cooled ones and shut down the 4 hot ones! it was cool. the temp needle went up but was sustained at a specific higher temp

 

Gotcha. That's pretty a nifty feature.

 

Every car should have that!

 

Speaking of the Northstar... I want one of those new STS soooo bad... I love it.

 

STS-V

 

That's what I meant to say.

Cadillac really stepped it up this time.

 

should have made it a 4.9 liter instead of a 4.4 though!

 

I'm having this problem right now. I have a new thermostat, water pump, and condenser fan (both fans work by the way) and my car is STILL overheating. I'm getting ready to take it to Acura today because I don't know what could be causing this problem. I have about 150K miles now. I was able to turn the heat on to cool it down but that's not working anymore. I don't want to ruin my car but the needle is seriously shooting up to the red mark now. I'm really tripping over it.

 

thats right....turn up the heater full blast..... will cool ur car down when driving if it start to overheat again........ u shouldn't drive ur car after u find out its overheating though......

 

is ur oil look milky..... milky = blown head gasket..... coolant mixing with the oil... if not u can try just to take out ur thermostat..... will take a little longer to warm up but coolant will be circulating constantly and thus ur car will be running at a lower temp.......

 

A cause for overheating that I've seen is when you suck a plastic bag up off the road into your radiator. The bag will block airflow through the radiator - although nothing is really wrong with your car.

That can be one exspensive piece of trash.

 

Is it actually over heating? is the coolant boiling over into the over flow tank? Are you low on coolant. Could be a faulty coolant temp sending unit. or a bad h2o pump

 

do u park it outside? same symptoms happened to my friends 00 TL ... he came to find out that an animal (a groundhog or something) had chewed up a bunch of wires and such causing it to overheat

 

Next time your car overheats just turn on the Heater Full Blast and you'll see the car tempature go down..

 

But thats not teh answer. You shouldnt have to turn the heat up to keep it from overheating. It should never get that hot unless there is something wrong

 

Last time my car showed those symptoms, i had to get my radiator replaced. Probably the last thing you want to hear