I am overheating badly. It will overheat when sitting in traffic and not all the time while driving. Recent things I tried are new t-stat, radiator cap, coolant. One thing i noticed just yesterday is the reserve tank was full and when I started out it was at the min mark on the tank. Could this be a head gasket issue? I did the timing belt and water pump back at 100000 miles so I am guessing it is not the water pump. That was PITA!
Also- questions i have: I notice that both fans come on at the same time and go off at the same time. Shouldn't one be running most nearly all the time coolomg the radiator? Where is sending unit for the coolant temp instrument gauge? Does anybody know where the fan switch is located? just wondering if I have a bad switch and that is why fan is not running all the time. Any other ideas would be great!

 

Whenever you have a chance because the engine is cold, check level in the radiator itself not the reserve tank.

Both fans are wired to start and stop at the same time. If ever only one is running, there is a problem. The easiest way to force the fans to run all the time is to disconnect the A/C compressor (so you don't put extra heat under the hood) and press the A/C button. Or jumper out the fan switch, which is located on the thermostat housing. The sender for the gauge is screwed into the end of the cylinder head on the transmission end of the engine. It has one wire.

 

Thanks for the info. After running some test including the ones above I think (hope) this is it:
1. tested coolant for hydrocarbons- it was negative so i might not have a head gasket issue.
2. drained coolant out of everything and tested t-stat and fan switch on t-stat. both check out good.
3. refilled with coolant exactly like the book says and appears okay with no air pocket.

My only question now is when radiator topped off and reserve tank at max level, after driving for 30 min the reserve tank is totally full and there is little air bubbles coming up from the bottom in the reserve tank. Any suggestions?

I will do a compression check tomorrow just to rule it out.

 

Update: drove it today and the level stayed the same in the reserve tank and needle stayed on mid point. One minor change was this: the car acted like it was running on 2 plugs for a few minutes. When I pulled th ecodes it said P0303-cylinder# misfire. Did this two times. Do you think there is any reason it is doing this now when I am having a overheat issue? Are they related somehow? HELP me! I need this car to be running good this week!

 

well here is the latest: put reserve tank to min level. raised front of car and ran it for 20 minutes with temp dial on hot. got a little air out of it but bled it really good this way. drove car for 20 miles and temp was good and reserve tank stayed right at min level. next 20 miles was a little different. ran great at first but at stops the needle would move up just a tad. looked at reserve tank and it was full and coolant coming out cap area. I am convinced I have a warped head or head gasket failure. also after the car sits from driving the next time you start it it spits and sputters but clears right up. most likely coolant getting into cylinder area maybe. does anybody out there have any other ideas?

 

Check your oil if it looks like your "making" oil or it looks like choc milk then you have coolant leaking into your engine from somewhere it could be a cracked head, bad head gasket, cracked block so on and so forth also if you had combustion getting into your coolant you would notice it bubbling out the radiato neck with the cap off (only do this check with it cold or after it sits and lets pressure off the system).