2000 GT Overheating Problem? Any help?

Hey guys,

Quick question. Yesterday I drove my car downtown and as I was on the freeway sitting in traffic i noticed the car's power was reduced and then all of a sudden it started to smoke from the hood. The temp gauge was in the red and the car was overheating. I pulled over the first chance I had and opened the hood. There was white smoke or steam (couldn't really tell) that was billowing out of the hood. I took my flashlight to see if i could see any holes or broken hoses and nothing was evident. There was coolant all over my engine bay, battery, etc. So, I let the car sit in a parking spot while I went to the Wings game (we lost :notnice:) and when i came back I checked under the hood again and didn't see any holes or broken hoses. I checked the coolant reservoir and there wasn't a drop left so i had it towed back to my place so i could check it out this morning.

As i was waiting for the tow truck i checked a few things and noticed the radiator fan was not freely able to spin because there was ice on the blade making it stick. I live in Michigan and we have had some bad snow storms lately, not sure how ice got stuck in there though. Also i went to my truck to get something and noticed my right exhaust pipe was completely blocked with snow. My apt complex plowed the snow and put a big mound of snow behind my spot and i remember hitting it as i left yesterday to go downtown. When i say it was blocked, i mean it was BLOCKED, i had to use a golf club from my trunk to poke a hole the packed snow out and then clear it with my hand.

So a few questions :

#1 Would the combination of the fan blade being stuck + the blocked exhaust, cause the car to overheat?
#2 When the car was overheating, was it possible it was just releasing the coolant from the radiator cap?
#3 Since I am out of coolant in the reservoir, how do i fill it up? Is there a spot to fill the radiator also, or do I fill the reservoir a few times? What is the process to do this? Fill it, turn on car, wait for it to go down, fill it again, etc etc? Do I have to worry about air bubbles?
#4 What is the best coolant to use? Peak, Prestone, Extended Life, Prestone Dex-Cool? I'd rather not worry about diluting it. I'd prefer to get a pre-mix.
#5 Anything else I should check or go-over?

Thanks for your help in advance.
 
#1 Would the combination of the fan blade being stuck + the blocked exhaust, cause the car to overheat?

Probably not the exhaust but definitely the fan.

Remember, the car has an 'H' (or 'X') pipe so the one bank will simply route its exhaust to the free side.

#2 When the car was overheating, was it possible it was just releasing the coolant from the radiator cap?

Hard to say but probable. If the temperature really did get into the red hopefully it wasn't spewing out from a warped cylinder head...

#3 Since I am out of coolant in the reservoir, how do i fill it up? Is there a spot to fill the radiator also, or do I fill the reservoir a few times? What is the process to do this? Fill it, turn on car, wait for it to go down, fill it again, etc etc? Do I have to worry about air bubbles?

The 2V generally isn't too hard to burp (unlike the 4V). Keep filling the reservoir, engine idling with the heater on full. Give the hoses a squeeze to help move air pockets. AFAIK, the thing is practically self-burping.

#4 What is the best coolant to use? Peak, Prestone, Extended Life, Prestone Dex-Cool? I'd rather not worry about diluting it. I'd prefer to get a pre-mix.

Any coolant of the same type that came out mixed in the proper ratio with distilled water is fine.

#5 Anything else I should check or go-over?

The engine may have been damaged by the excess heat. Keep an ear out for sounds and and eye out for leaks, coolant in the oil (milky dipstick), oil in the coolant etc.

Also check the fan and its circuit (fuse/breaker). Make sure being stuck like that didn't damage anything or leave it inoperative.
 
So a few questions :

#1 Would the combination of the fan blade being stuck + the blocked exhaust, cause the car to overheat?
#2 When the car was overheating, was it possible it was just releasing the coolant from the radiator cap?
#3 Since I am out of coolant in the reservoir, how do i fill it up? Is there a spot to fill the radiator also, or do I fill the reservoir a few times? What is the process to do this? Fill it, turn on car, wait for it to go down, fill it again, etc etc? Do I have to worry about air bubbles?
#4 What is the best coolant to use? Peak, Prestone, Extended Life, Prestone Dex-Cool? I'd rather not worry about diluting it. I'd prefer to get a pre-mix.
#5 Anything else I should check or go-over?

Thanks for your help in advance.

#1 unlikely because the weather is cold enough where the radiator minus fan should have had no problem keeping the car cool. With respect to the exhaust, one clogged tail pipe will not really do anything except reduce horsepower. These cars have a crossover pipe (h if factory, or possibly X if you have an aftermarket midpipe). Therefore if you were to clog one tail pipe exhaust could still escape through the other side.

#2 also unlikely. If you had that much coolant under your hood something is wrong. The white vapor was likely steam coming from the leak and from coolant boiling on the exhaust manifolds.

#3 yes fill it using the reservoir and it should dripple down into your radiator. You may have to run the car to circulate the coolant and continue to add over the course of a week or two. I've also had good luck squeezing the large upper coolant hose a few times to basically manually pump the air towards the reservoir.

#4 doesn't really matter what coolant you use as long as it's mixed 50/50. Until you isolate that leak I wouldn't spend much money on coolant.

#5 I'd check your coolant hoses, check to see if you have the plastic coolant crossover (where the t-stat resides) on your intake manifold as the plastic ones were prone to crack, check the heater tube that attaches to the rear of the intake manifold, and finally are you sure you had 50/50 coolant in your car before this happened? You may have had frozen coolant in your engine resulting in engine or coolant system damage .
 
Thank you also N8Dogg.

I will try both your's and trinity_gt's recommendations.

In regards to your question, i am sure that mixture was 50/50 previously because last year around this time I had a coolant flush at a local oil change shop. I haven't had any problems until now.

Also, I was on the freeway doing 70 or 80 for about 20-30 minutes then I sat in traffic going less than 5 mph for about 30 minutes and I am wondering if the engine was super hot and couldn't cool off due to the fan not working? I should have posted more details about how I was driving the car.

Anyway, I'm off to the store to get some coolant and I'll post my results shortly.

Thanks again to both of you. :nice:
 
Thank you also N8Dogg.

I will try both your's and trinity_gt's recommendations.

In regards to your question, i am sure that mixture was 50/50 previously because last year around this time I had a coolant flush at a local oil change shop. I haven't had any problems until now.

Also, I was on the freeway doing 70 or 80 for about 20-30 minutes then I sat in traffic going less than 5 mph for about 30 minutes and I am wondering if the engine was super hot and couldn't cool off due to the fan not working? I should have posted more details about how I was driving the car.

Anyway, I'm off to the store to get some coolant and I'll post my results shortly.

Thanks again to both of you. :nice:

If you were going less than 5 mph for 30 minutes that could definitely cause the underhood temps to rise. Was it traffic due to a snowstorm or something?
 
Definately check the cooling fan, specifically the motor. You can replace the motor seperately from the fan and it isn't uncommon for the motor to go bad. I just had to replace the motor on my 97 GT last year.

I am guessing you had ice on the fan from the coolant tank burping all our water out. Some of the water stuck to the fan and froze.

I am betting the fan motor died and this is the first time it should have turned on but didn't.
 
The fan has 2 ON points, one for the low speed and one for the high speed. If you let it sit and idle for an extended period of time, then you should see the fan kick on a little above the middle marker on your temp gauge. The computer settings are probably for something like turning the low fan on at 205 and the high fan on at 220. :shrug: I sometimes hear mine kick on at lights or drive threws where I am idling for a long period, and the factory dummy gauge is pointed about in the middle.

Another option is to turn the AC on and that works well in the summer when the compressor runs. However, I don't know if the fan runs if the compressor doesn't run... Worth a try. If the fan kicks on, then you know it is good. If the fan doesn't turn on, then check another way.
 
So I added some coolant (50/50 mix) and the car sucked down 2.25 gallons. I then proceeded to let the car run with the fan setting on high in heat mode. While the car was running ~10 minutes the radiator fan never kicked on. I am not sure at what point this should kick on.
I went into the car after about 10 minutes and the vents were blowing cold air and the coolant light was still on. So I turned the car off for 20 seconds and turned it back on and the coolant light went off but the car was still blowing cold air.

There were no leaks and the car didn't require any more coolant. I did squeeze on the larger hose but if seems like it was getting to the engine because of the thermostat? Could that be the issue, and how would I test that?

I read somewhere that it is a good idea to disconnect the battery after you replace to coolant to reset the ECU.

Would there be anything else I should check? I am going to unplug the battery for a bit and see what happens.
 
I added coolant by pouring it into the reservoir until it was near the fill line, then i started the car and added coolant as the radiator sucked it from the reservoir.

I decided to let it run for 20 more minutes or so while carefully watching the temp gauge and the coolant level. The vents were on heat in the high speed. The car started to warm up and the vents got warm and then warmer and then hot (nothing out of the ordinary). I was starting to think it was fixed and maybe there was just some air in the system. But once the car got to 72 Celsius (162F) it started to smoke a little from the underneath the overflow reservoir, right where the actual radiator is. I looked for leaks and didn't see a drop of coolant on the floor, so it's not leaking anywhere. I ended up shutting the car down so it didn't overheat and start to spew coolant everywhere.

The radiator fan never kicked on and I am not sure if there is a way I can test this to see if it even works at all. I did notice that Fuse #1 in the Power Management Fuse Box (located to the right of the engine) 50A Red Fuse was blown and that controlled the "Engine Cooling Fan" so I replaced that thinking that was the problem and that didn't solve the problem with the radiator fan either. I replaced that fuse prior to letting the car run for 20 minutes.

So since I am getting warm/hot air from the vents does that mean my thermostat is good? I bought a new one just in case but I didn't install it because it got too dark and I didn't want to waste any time if that wasn't the problem.

So I am stuck now.

Current Symptoms:

Once car reached 72 Celsius/162F it started to smoke from under the reservoir
Radiator Fan doesn't turn on (even after 20 minutes of idling). It is about 25F out right now.


Also:
No Leaks
Radiator overflow is at the correct line


additional note: I was able to get the exact temp of the engine by using the digital tool when you start the car and scrolling through the gauge settings.

"To enter the HEC Dealer test mode,
1. Depress and hold the instrument cluster SELECT/RESET button,
2. Turn the ignition switch to the RUN position
3. Continue pressing the SELECT/RESET button (5 seconds) until tESt is displayed in the odometer.
Note:SELECT/RESET button must be released within 3 seconds of the odometer tESt display to begin the dealer test mode.
4. What will happen next is all your analog needles will "sweep" to their max positions and then drop back to normal. The digital readout will say "GAGE"."

You can then scroll through the other menus to get other info including temp.
 
I think the car needs to be hotter for the fans to kick on. The stock thermostat is a higher temp than 162.

Yes. If you are feeling heat, then chances are the thermo is working properly. Also touch the upper and lower coolant hoses. They should be the same temp.

Does the fan spin free?
Do you have a volt tester?
 
I think the car needs to be hotter for the fans to kick on. The stock thermostat is a higher temp than 162.

Yes. If you are feeling heat, then chances are the thermo is working properly. Also touch the upper and lower coolant hoses. They should be the same temp.

Does the fan spin free?
Do you have a volt tester?

Yes the fan spins free now, it previously did not due to ice. I do have a multimeter.

Why would the radiator still be smoking though? That is what is stumping me.