wizurd

Im overheating at an idle at lights.......... as soon as i step on it drops down to normal........ is this a thermastat misreading and i need to replace?? water pump going?? just dont tell me its a head gasket or a head!!! need some advice./

thanks

Mulder

You need to post more information- what car you have, mileage, any mods, etc.

n/m, checked your profile and see you have an 02 WRX but you really should have mentioned that in your post. It would still be helpful to know the mileage and whether it is stock or modded.

Was any recent service done, particularly on the cooling system? There could be air trapped in the system although if that were the case it would most likely overheat regardless of whether you were moving or not.
Check to see if the cooling fans are coming on, if they aren't this could cause overheating after extended idling. However if it's happening after just a short time at a light I doubt it's the fans.
Of course be sure that the system isn't low on coolant, and if it is look for leaks.
And yes it is possible that the cause is a bad head gasket. Not that common on WRX's but it can happen.

All of this is just speculation, to get this properly diagnosed and fixed you need to get the car into a shop, ASAP. You don't want to drive it around that way for very long.

wizurd

Sorry..... it was just late last night..... .my car is an 02 wrx wagon with 33000 miles and i think my 3yr just passed on the warranty..... the car is lightly modded with cat-back exhaust and cold air intake only performed on the motor rest is cosmetic.

I was low on coolant (guess i neglected to check fluids last oil change) so the resevior was empty......... i did fill it...... then it seemed to go down some...... then refilled it (hope this wont cause air pockets???)

The car is still surpassing the "normal" barriers at an idle pretty consistently with no evidence of leaks and the car seems to be running fine other than this problem. Also fans are working and kicking on with or w/o A/C engaged...... although i turned the car off when it was past normal operating temperature and the fan doesnt stay on....... should it not?? Also after the car is turned off i can here some sort of gurgling (very very faint) coming from the turbo area..... which to me sounds horrible......... but im also a pesimistic and hopefully just naive to the fact that the car has always done this.

this has my brain overheating as welll!!!!

Mulder

The reservoir being empty isn't a good sign, but you can't really tell just from that how low the coolant is. With the engine cold, remove the cap on the reservoir atop the engine (I assume you don't have the cap on the radiator, unless it's been replaced with an updated one), and see if there is coolant there right up to the top. If not fill it through there slowly, then run the engine until the thermostat opens. Top it off if necessary, then fill the bottle to the line. If the level went down low enough you may need to "burp" the system to purge any air that got in. The gurgling may indicate the presence of air although it is normal for coolant to circulate through the turbo for some time after the engine is shut down.
There can be leaks even if you don't see them. Look carefully at the radiator tank seam area which is a common point of failure on the 02 radiators w/o the cap. Also check the hose clamps for tightness, there can be seepage at the hose ends that goes unnoticed.
It is normal for the fans to go off when you turn off the ignition, even if they are running at the time.
If the problem still exists after the system is filled and purged, you'll need to look further.

wizurd

I was already out there refilling the system a second time after my last post....... let cool and filled at both ends) reran the car with no problems.......... im thinking that was it........ makes sense since little fluid with no circulation at idle would make that little of liquid heat rapidly...... and then cool rapidly once moving.......... but took for 3 drives and no problem after the purge............ think im in the clear....... u would think living in the desert i would be more on top of the cooling......... but it has been such a nice winter!!!

And that statement about the coolant circulating in the turbo after turning off would explain the faint gurgling i heard of liquid.

If this problem does come back ill be back......... but i dont think youll be hearing from me unless it does which is the best thing

Thanks Mulder..... not that i wouldnt have solved this one, but just nice knowing others concerned and willing to help.

Seth

Mulder

Good to hear, but be sure to check very, very carefully for leaks. It isn't really normal to lose that much coolant under normal conditions. When I serviced mine, I removed the hoses because I was changing the radiator and discovered that they had apparently been seeping from the ends for quite some time. I had no idea until I took them off and looked.
You also unfortunately can't rule out the possibility of head gasket issues, so just keep that in mind. After you give it the once-over and address any leaks that turn up, keep a close eye on the level to be sure it isn't still going down.

BelfryExpress

Dumb question.


Are there aux fans on your car? If it has them, are they coming on? If not, check the relay.