6G Celicas Forums

Greetings.

Car: 1997 Celica GT 2.2 5sfe, 125k miles.

Problem: Overheating; The temperature gauge has never gone above the halfway mark the entire time I've own the vehicle (and does slowly climb to 45% as it warms up from a cold start, then sits there, even as the coolant gets hotter and starts to boil away).

A few weeks ago I thought the engine compartment seemed a lot hotter than it should be. The metal short ram air intake tube (in process of converting to CAI) was far too hot to touch.

Soon after I checked the coolant and noticed what appeared to be rust, so I decided to do a coolant flush (probably should've just replaced the radiator at this time). I flushed both the engine and radiator with a hose until clear liquid came out (going both directions through the engine). Ran the car for a bit without the thermostat installed. Then I installed a new thermostat: 180F with jiggle valve, and topped off the coolant (didn't bother to test the old thermostat since it was cheap and easy).

I continued to drive for about a week after that (mostly not more than 7minute trips to work and back) until one day I got home from a 30min drive, opened the hood, and noticed the overflow reservoir was boiling. After it cooled down I removed the radiator cap and noticed it was broken so I bought a new one, and installed it. During that week I do remember the hearing the fan(s) come on. Sometime shortly after this I noticed when I turned the AC on, there was a bit of a louder noise while it operated (which I only heard with the windows down and at low speeds or while stopped).

Drove to work and back a couple more times, then after another 30min drive, I got home, and there was steam coming out of my hood. The radiator (which looked like it could've been the original) had multiple cracks along the top where the coolant/steam was ejecting. So I drained the coolant, did another flush and replaced the radiator with a new one. I also removed the reservoir to properly clean all the rust and what not out of it. [I have changed the oil once before all this happened, and again recently, and never has there been any coolant or discoloration of the oil.]

I filled up the radiator (and poured some water in the overflow) and started the car with the cap off. I was only able to get about what seemed like 3 liters or so into the system. The top hose began to get very hot and then it started steaming/boiling out of the top of the radiator. The fan did not turn on. The temp gauge showed normal. My initial thought was that the new thermostat wasn't opening, since that bottom hose was still cool, and thus, the hot coolant wasn't reaching the sensor down there to turn the fan on. (I did detach the plug to the sensor and turn the ignition on and the driver side fan turned on and stayed on [is that right that only one turns on unless the AC is on?]).

I removed the thermostat and did the water boil test with a thermometer in the water and it opened at about 183F. Just for kicks I bought another one without a jiggle valve for $5 and it opened at 180F exactly. I could run water through the radiator and the engine so I knew there wasn't any blockage going on there. I have tried reinstalling both of the new thermostats and filling the system, but the same thing keeps happening: bottom hose stays cool, top hose gets hot, temp gauge normal, and steam/boiling starts. I have not found any rust since replacing the radiator so I assume that was all caused by the old radiator.

Today I tried one more time, thinking maybe there's just a big air pocket. The car was already at a slight incline facing up hill, so I then removed the thermostat (to make sure it wasn't blocking the coolant), reattached the hose and filled the system with water. Then I installed the thermostat again and started it up with the rad cap off. It did the same thing (heated to boil in the top, but the bottom hose stayed cool and temp normal), but it seemed like I was able to get more fluid in there than all previous attempts. I have not tried this process with the coolant sensor plug detached at the bottom of the radiator, but would not having the fan on really have anything to do with that bottom hose staying cool? (I'm assuming the sensor works, but the hot coolant is simply not circulating far enough to reach there through that bottom hose).

When the coolant ejects after it heats up with the cap off, it comes out in pulses every second or two, not a constant stream.

What more diagnostic tests can I do and what further information can I provide to you?

I have been searching this forum and Google for 3 days, and found many people with similar problems, but not one with all of my exact symptoms.

I should mention, about a week before this all started I did feel like I had a loss of power once it warmed up (except while traveling at freeway speeds).

Other notes, the AC has always blown cold and the heater, hot. No leaks have been found of any kind. Have never seen any smoke from the exhaust.

List of items replaced:
-Thermostat (Napa part number ATM 1542403)
-Radiator (Napa part number NR 2543)
-Radiator cap (Napa part number BK 7031728)
-Coolant (green)




*EDIT: I'm thinking it's gotta be the water pump since I confirmed no blockage and that the thermostat works fine, even though there are no unusual sounds or leaks...

This post has been edited by 97Corners: Aug 10, 2014 - 5:43 PM

The water pump cannot fail in this manner, it is an impeller driven by the timing belt.

Could be the headgasket. Unplug the sensor located on the bottom tank of the radiator, this should cause the radiator fans to run nonstop. If both fans run, try driving it around like this and see if it continues boiling over. If it continues overflowing I would suggest checking the coolant system for exhaust gasses.



When you fill the coolant system, make sure the heater is turned on and blowing.

i can see the huge crack in your radiator. replace it

This post has been edited by Smaay: Aug 5, 2014 - 11:22 PM

Only one fan (on driver side) comes on when I unplug that sensor. I have been making sure the heat is in when I've been trying to fill it.




The one in the picture is the old one; I haven't broken the new one just yet. =P

Try burping it again. I had a similar issue with a Mark III Supra. I had a lot of growling behind the cluster and burped the system enough to rid the car of the growling, but there was still A LOT of air in the system - causing overheating problems. I had to park at a very extreme angle to get this settled (about 35%). I went sideways up this huge hill on UNCC's campus and cut it uphill at the last second, I thought I was going to slide down! Anyways, I opened the radiator cap and only turned the engine over for half a second, without letting it turn on completely and starting running. I topped off the radiator after each time that I turned the engine over. After this, I no longer had any issues. The air bubble could cause poor circulation and overheat a pocket of water.

If only one fan comes on, try this again with the a/c on and the wire unplugged.
If both fans dont run you are having a cooling fan issue.

With AC on and the bottom coolant sensor unplugged I still get only the driver side fan on. I did move the car to a steeper angle and slowly massaged all the tubes (both heater and both radiator hoses) and was able to get a bit more fluid in. The bottom hose finally feels like it's completely full of water instead of air. Almost seems well enough to test it on a drive longer than around the block... or should I figure out why the AC fan on the radiator isn't turning on first (seems like as long as I don't use the AC, it shouldn't matter if that fan works for now)?

*Edit: the fuse for the condenser cooling fan (fuse 14, 30amp assuming it's the right one) is intact, though there is green/corrosion on the metal inside it. Is it possible the temp sensor that goes to the temp gauge is faulty since it never goes above normal temp even when overheating?

*Edit 2: Just drove around for several minutes with the coolant sensor unplugged. Got back, popped the hood and noticed both fans are going now (whether the ac was on or off), instead of just the one.

*Edit 3: Drove to work and back and it started to overheat on the way back. For the first time, the temp gauge started to climb fairly quickly above normal. I turned on the heat, pulled over, turned the car off (but turned the ignition back on so the fans would keep going). The top radiator hose did look like it had expanded a bit from the heat and pressure (never noticed it expanding like that before). Both fans do continue to run at the same time regardless of AC (with the coolant sensor unplugged). Waiting for it to cool off and will drive it the rest of the .9miles home later tonight. The bottom hose was pretty warm for the first time.

This post has been edited by 97Corners: Aug 6, 2014 - 4:39 PM

Sounds like a bad cooling fan. Figure out why the one is only working intermittently.

also, cheap radiator caps don't necessarily have a vacuum valve that works. so it doesn't suck coolant back in from the overflow bottle when you shut it off and it cools down. get that from Toyota, or a salvage yard.
and this test right here https://www.youtube.com/watch?v=1_SIwHMLmkM will prove whether or not you have exhaust pushing into the radiator.

mine has head gasket issues and will do the same thing if I drive it hard (above 3k rpm). it puts so much exhaust into the radiator that the temp gauge (which is at the top of the motor) shows hot, while the radiator fan switch (which is at the bottom of the radiator) still doesn't see it's hot enough to turn the fans on.
its just that the top radiator hose is full of exhaust, and there's still coolant in the radiator. ive managed to get by shifting at 2200 and not going too fast. and if you flush the radiator and it gets worse that may be because it had already been stop-leaked at some point in the past.

Right you were VavAlephVav; it was a blown head gasket. Only just now is the oil and coolant mixing when I took off the cap to do the block test. Also checked the plugs and what not... definite coolant mixture. I want one of the metal head gaskets for the 5sfe in the 99 Camry, right? (And can I get the whole gasket set for the Camry, or does only the HG from it fit)?

I couldn't find any fault in the wiring/relay/fuses for why that one fan wasn't working before (went through the troubleshooting from the manual)... I'll check things over again after replacing the head gasket (and probably water pump/timing belt I guess).

several aftermarket companies have a Multi Layered Steel (MLS) gasket. if you call the dealer and ask for your specific year they will still try to give you the old cork/rubber one. most people say if you go to Toyota you can ask for the 98+ Camry headgasket and it will be MLS.
if you get an aftermarket Kit with all the gaskets some of them will probably be the cheap paper ones, that's what I saw when I looked into it. so maybe some things like the throttle body, and intake gaskets I'd go to Toyota and get the nice metal ones they still aren't real expensive.

idk wtf was the deal but Dodge and others all did the same thing on their aluminum head 4 cylinders and used some crappy gasket for several years. I don't know if I've seen one with more than 100k miles on it that Didn't need a head gasket. On my Dodge Neon I had the dealer replace the head gasket twice under warranty, and 20k later it was broke again.

this time im kinda miffed at myself for letting other people talk me out of using stop-leak sooner, I'm getting a whole new motor though I just gotta keep this one running for another month.

This post has been edited by VavAlephVav: Aug 12, 2014 - 9:48 PM