1990 Celica Cooling Problem

[NationwideClyde]

My friend's 1990 Celica GT (4cyl/auto), w/ 170k on it, (130k of it on a '91 engine), has developed, over the course of driving almost 3,000 miles from Wisconsin to California, a rather concerning cooling problem.

In Nevada, a shady service tech at a Chevron noticed antifreeze residue caked to the left-front wheelwell and immediately suckered my friend into paying $150 for a coolant system flush and a new thermostat.

Things were AOK until two days ago when we noticed rather a lot of steam escaping from the end of the hose running to the overflow bottle (the hose runs through the cap and is open-ended...is this normal?) Shortly afterward, we noticed the temp. gauge had shot up into the red. We immediately stopped- it took almost a gallon of 50/50 water/AF mix. Since then, he's put 400 miles on the car w/o incident (he's a tech for CompUSA).

Anyhow, he's counting on this rig to hang together for him- what sort of problem do you guys think it has, can we fix it ourselves, and what should it cost? The electric cooling fans are kicking in as normal; the cooling system seems to be otherwise fine aside from on rare occasions steaming coolant out the end of the overflow hose. He wondered if it was meant to be capped; should we be concerned about too much pressure in the system? Is the radiator biting the dust?

Tim Hansen

[Leeky]

Hummm i had the same problem in a company vehicle once. Sounds like the head gasket is shot.

How hot is your radiator getting?

If its cool then you must be getting a blockage somewhere. Thus water isnt being cooled causing the car to overheat.

Or if the radiator is hot then the radiator must be getting rid of some heat.

A mate of mine had the same problem on his ford escort (Fix Or Repair Daily) and the main dealer couldnt fix it. They said that the engine was so old and worn that it was beyond economical repair. He ended up forking out for a recon engine which did sort the problem.

[Vinnie Cooper]

I'm having a similar problem at the moment. Vincenzo (er a dodgey 92 Jap import SR spec celica) started overheating just a few days ago after many wonderful (and cool) miles driving.

Having identified the problem as the electric fan not coming on I reckon its the fan switch sensor on the radiator. On pulling the cable off the sensor one of the fans comes on (I think the other kicks in with the A/C on).

All was sorted I thought until the replacement sensor gets here....

However after about 6 miles 'normal' driving she started warming up again (with the fan on constantly). I checked the coolant and saw that it was a pint or so short of full and topped it up. (presumably when overheating the cap had been releasing the pressure which give the bubbling you mention). Unfortunately this behaviour keeps re-occuring so I now suspect the cap having been called to activate once in its otherwise sedentary life is venting at quite low temp and pressure and needs replaced.

Does this seem sensible to anyone else?

[DaveG]

Possible head gasket. Could be leaking coolant internally into on or more of the cylinders, in which case it is blowing out your exhaust.