Yep, the hot AZ weather is wreaking havoc on my cooling system. Driving down the interstate I will be fine cruising at 80mph, maybe raising the temp up a little bit, but as soon as I throw on the A/C it climbs up above 236* and throws on the CEL. Also when I drove to SoCal going 115 I was overheating too. Kind of scaring me, because the weather is only going to get hotter.

Do you think my problem is:

1) Greddy FMIC blocking radiator

2) Thermostat going bad (I'm hoping for this one)

3) Bad mix of 50/50 (store bought) antifreeze (it might be mixed with some other generic stuff I had in before I did a radiator flush)

4) Other - Please explain.


Do you think I should just replace my thermostat first and see if that cures it??

TIA

Check the thermostat. It's super cheap ($15 from the dealer to replace) and can be done in minutes. Might as well get a new one.

I replaced and upgraded both fans, flushed the coolant several times and did so many repairs only to find out it was the $15 thermostat.

Try that first. More water in the mix helps too but in that summer desert heat, more water will boil over faster. Add some water wetter to the mix as well.

Originally posted by FlyinEsi
1) Greddy FMIC blocking radiator

This is a common issue with Greddy FMIC on our cars.

Originally posted by FlyinEsi
2) Thermostat going bad

Very possible

Originally posted by FlyinEsi
3) Bad mix of 50/50 (store bought) antifreeze (it might be mixed with some other generic stuff I had in before I did a radiator flush)

Just flush it, and refill with new stuff, it's easy.

Originally posted by FlyinEsi
4) Other - Please explain. Do you think I should just replace my thermostat first and see if that cures it?? TIA

Yes. Also, use some water wetter, it's cheap and i have seen people post 10 degree drop in temperature regularly.

I run two slim fans(13" and 10", both as puller), no thermostat and a 80/20 mix of water/antifreeze. I also cut the front bumper:



Solved all my overheating problems.

Edit: Also add 30 to your coolant offset so the fans will come on at about 175 instead of 210 like normal.

Originally posted by FlyinEsi
Also when I drove to SoCal going 115 I was overheating too.

how do you keep your EGT's low enough to cruise at 115?

Originally posted by Vandy420a

Originally posted by FlyinEsi Also when I drove to SoCal going 115 I was overheating too.

how do you keep your EGT's low enough to cruise at 115?

I don't know about low, but the EGT's were at about 1500-1550. I'm not too worried about my EGT's...as long as the needle doesn't creep above 1650-1700.

But the car overheats on simple pulls in like 3rd/4th gears with no A/C turned on or anything. Kind of ruins all of my interstate fun I try to have.

I think I'm going to cut out the rest of my bumper too...looks good on jsupertan's car.

Originally posted by FlyinEsi But the car overheats on simple pulls in like 3rd/4th gears with no A/C turned on or anything.

Sounds like thermostat. No coolant being routed to the radiator and any load on the engine and you are seeing instant overheating.

Originally posted by FlyinEsi
I think I'm going to cut out the rest of my bumper too...looks good on jsupertan's car.

K but that won't do anything to keep your car from overheating.

Thermostat, water wetter, compression test/headgasket check, aluminum radiator, vented hood. In that order pretty much.

Originally posted by Jeff_99gs

Originally posted by FlyinEsi I think I'm going to cut out the rest of my bumper too...looks good on jsupertan's car.

K but that won't do anything to keep your car from overheating. Thermostat, water wetter, compression test/headgasket check, aluminum radiator, vented hood. In that order pretty much.

or move back to wyoming where it never gets hot... haha

All good advice up there^^^. Spal fans aren't too expensive and pull alot more air. After replacing the thermostat and changing the coolant mix, pick up a couple of them.

Originally posted by eclipzGST
All good advice up there^^^. Spal fans aren't too expensive and pull alot more air. After replacing the thermostat and changing the coolant mix, pick up a couple of them.

I already have one 12" spal fan, and the other is the stocker I think.

Water Wetter?? Do I get that at autozone or what???

Vented Hood?? Really...do I have to...will definitely save that for last...

Alum Radiator - I will be looking into that pretty quick.

ONce you cahnge the thermostat or eliminate it like i do, if it still overheats change you mixture to about 80/20 with more water...preferably distilled. IF that doesn't work, I would switch the stocker fan to another spal fan since they flow better. Use DSMLink to offset the coolant +30 to make the fans come on ealier. also cut the bumper alittle more in a way that will allow air to hit the radiator. That solved my overheating problem with my fmic. Aluminum radiators do not help with the overheating. IT has not been proven...save that and the hood for last since they will cost the same. But like i said, i don't overheat no more with stock radiator and neither have a few others with the same fmic as me.

Another option cheaper than a vented hood would be to raise up the hinged side a little to let air flow through. It would just take a "little" bit and would hardly be noticible. I've heard of others doing this a LONG time ago. I remember seeing pics also but forgot where the hell I saw them.

Originally posted by eclipzGST
Another option cheaper than a vented hood would be to raise up the hinged side a little to let air flow through. It would just take a "little" bit and would hardly be noticible. I've heard of others doing this a LONG time ago. I remember seeing pics also but forgot where the hell I saw them.

My college roommate did that with his 97 TSi AWD and it did nothing but let water run down the firewall. Never fixed his overheating issue, but left quite a lot of rust all over the firewall. :)

Originally posted by BigBald
Aluminum radiators do not help with the overheating. IT has not been proven...

Actually it completely fixed my overheating problem. In fact the car barely stays warm enough to keep the damn thermostat open with the Fluidyne installed. The Fluidyne is not only all aluminum, but it is thicker as well.

Also I have a stock thermostat installed (original with 104k miles on it), I never cut my bumper larger or put holes in it, I retained the stock bumper reinforcement, I keep a strict 50/50 mixture, and I never needed a vented hood. I do use water wetter though. My awful overheating needed nothing but a Fluidyne and it is gone forever. I stand behind that product and recommend it to anyone.

But that is just me.

Okay, can I get a second opinion here...a friend of mine told me if the car pukes antifreeze after hard runs, which mine does just after a long hot drive down the interstate with the A/C on, it means I need a new head gasket...can anyone confirm this????

Originally posted by FlyinEsi
Okay, can I get a second opinion here...a friend of mine told me if the car pukes antifreeze after hard runs, which mine does just after a long hot drive down the interstate with the A/C on, it means I need a new head gasket...can anyone confirm this????

more than likely... yes.
But, if it's your thermostat sticking, that would also cause you to piss out the overflow.

alright, before I contribute to this thread anymore, I'm changing my damn thermostat...going to go pick it up tonight...maybe swap out tomorrow. I'll give the 411 when I'm done.

Thanks guys.

I would also replace your thermostat cap while you are at it. That is what caused me to puke antifreeze.

Originally posted by Jeff_99gs

Originally posted by BigBald Aluminum radiators do not help with the overheating. IT has not been proven...

Actually it completely fixed my overheating problem. In fact the car barely stays warm enough to keep the damn thermostat open with the Fluidyne installed. The Fluidyne is not only all aluminum, but it is thicker as well. Also I have a stock thermostat installed (original with 104k miles on it), I never cut my bumper larger or put holes in it, I retained the stock bumper reinforcement, I keep a strict 50/50 mixture, and I never needed a vented hood. I do use water wetter though. My awful overheating needed nothing but a Fluidyne and it is gone forever. I stand behind that product and recommend it to anyone. But that is just me.

how big is your FMIC? A friend of mines went with the fluidyne immediately and it did absolutely nothing for him. I opted to add the second slim fan and change the mixture before actually upgrading the radiator since I seen it did not help him out. Colling is a paint in the ass sometimes to fix. There are people who still over heat and have done everything mentioned in this thread.

My FMIC is pretty much the biggest you can fit on a 1G without being stupidly big. It is the 2-216 Race core.






I guess 1st gens just have a better cooling system then? :shrug

Originally posted by Jeff_99gs
...

Isn't it you that says it's usually cold where you live? Or colder than normal?

Nope I live in Maryland. 100 Degree summers with 100% humidity.

Originally posted by Jeff_99gs
Nope I live in Maryland. 100 Degree summers with 100% humidity.

Huh, I forgot who I was thinking of then. There was a discussion in the chat about what the weather was like this last winter, but I forget who said what.

Originally posted by Jeff_99gs
My FMIC is pretty much the biggest you can fit on a 1G without being stupidly big. It is the 2-216 Race core. I guess 1st gens just have a better cooling system then? :shrug

excuse me while i go clean up. ;-)

i want that IC, where do you live again? i might have to *borrow* it. :D

I definitely stand with Jeff on the Fluidyne radiators. On a 50 degree day I can drive all the way to Houston (100miles) and the needle never reaches the halfway mark, and this is with the radiator fan off. (switch controlled)

Well, I'm just hitting this full bore.

I have ordered...

Greddy Braided Radiator Hoses
Greddy Radiator Cap
Greddy Oil Cap(hehe just because)
Watter Wetter
FailSafe Thermostat (180*)
Thermostat Ring

If all this doesn't work...Fluidyne, here I come.

If that doesn't work...this car will be up for sale!

NOT!

Bah....who needs a thermostat.....lol.

Originally posted by BigBald
Bah....who needs a thermostat.....lol.

You know, in all reality, with how warm it is down here in AZ, do I really NEED a thermostat?? It is just used to help the block heat up quicker, right????

there is a huge thread on this on the DSMlink board....check it out.