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New fmic and cooling problems on the highway. Up to 230*

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96gstdsm

15+ Year Contributor
808
2
Aug 7, 2006
monroe, New York
Just got a big ssac fmic installed. I am now having some cooling problems. When I am stopped or going slowly in traffic etc the temps are around 210* or so. For some reason though when I am going on the highway just cruising the temps go up as high as 230*
Shouldn't it be cooler on the highway? I always figured that the cooling problems would be when stopped or going slowly. Could this be another problem? The thermostat was replaced I know. What temps are safe or unsafe? Could it be that I just need to bleed the coolant system and refill? What is the deal with the mod of drilling a 1/2" hole in the thermostat housing? Anything I can check before I assume it is just not getting enough air somehow on the highway? Obviously I am aware that the fmic is blocking a lot of air, but from my understandings most people don't have any issue on the highway. Traffic I can understand more but not when moving with all the air coming up from underneath and all. Also the temps when on the highway go up and down for some reason. Like from 218* to 226* about. The stock gauge shows it going from just over the middle line to about 3/4 the way to hot and then just back down again and repeats. My logger shows that the temps are changing as the stock gauge changes also.
 
I have the same problem. I am fine on the street, but on the highway it gets hot. I thought the same as you. If someone can help this guy it will be a double whammy.

But it could possible be something else. And just started when u did the front mount install. I noticed it with these cars, they love to bust balls LOL....
 
Yeah I'm assuming it is cause of the fmic but I did a ton of other things at the same time. 6bolt block, built head with bc 272's, new turbo, full exhaust, fuel etc. Could any other mods cause overheating like this?
Not quite sure what would be causing it to overheat only really on the highway. Still a little over 200 when driving around but never up to the 220* area or anything.
 
Could be the timming ot hg, but i owned a subie and the hg went and i want able to drive it 4 miles with out it overheating and spitting coolant everwhere. I will be driving for like 45 mins or more, before it decides to get hot. But i think its the front mount. Some people get lucky and some dont. Its a good idea to keep the stock fans on there. I noticed they work best. I kinda want to upgrade the rad, but i dont want to pay 300 or more for a rad.
 
Could be the timming ot hg, but i owned a subie and the hg went and i want able to drive it 4 miles with out it overheating and spitting coolant everwhere. I will be driving for like 45 mins or more, before it decides to get hot. But i think its the front mount. Some people get lucky and some dont. Its a good idea to keep the stock fans on there. I noticed they work best. I kinda want to upgrade the rad, but i dont want to pay 300 or more for a rad.

Highly doubt it is the head gasket. Had a mitsu mls which didn't seal so sent my head out to be built. Got it mirror polished and the block was decked. I got it sealed with an oem composite gasket and arp head studs. No smoking out the exhaust or anything. Billowed white smoke out when the headgasket didn't seal last time. Compression was basically perfect also.
So really must be the fmic, just looking to see if others have had this problem on the highway with their fmic's.
 
I had the same problem until I did one thing.

Swapped out the 2GA bumper for a 2GB bumper.

And yes, Im being serious. I used to run at 217-219 all day long but that has been fixed.

Another reason why, is because you still probably have the a/c condensor in place.
 
I guess you took out the ducting that goes to the radiator. It makes it so the air goes from the front mount to the radiator. Otherwise the air will just go out the side and bottom. You just need to make some kind of ducting to make the air go to the radiator.


http://www.dsmtuners.com/forums/showthread.php?t=245981&highlight=cardboard
http://www.dsmtuners.com/forums/showthread.php?t=237780
http://www.dsmtuners.com/forums/showthread.php?t=248064&highlight=koyo
http://www.dsmtuners.com/forums/showthread.php?t=224201&highlight=front+mount+heating
 
Start with a coolant flush. You can use the bottles of flush that is sold at autozone/pep boys. Just put it in your coolant and drive passively for a couple days. When you flush, mke sure to warm up your car after every exchange of coolant so the head is flushed along with the radiator. Do so until you get clear water. Mix 40/60 or 50/50 coolant:water with a bottle of water wetter. Make sure to use distilled water on the flushes and the refill.

You can also try to wire your two fans together, although at anythng more than 40mph it's probably not going to help.

Making ducting like bbray said will help alot.

This isn't a rare problem. Lots of people with the SSACFMIC have had overheating in hot weather. Going too hot CAN hurt your motor - warping head, excess pressure, ect. I overheated similarly to you when it was 95+ degress out, which was fixed a flush.

Come back if this doesn't help.
 
i don't know how you feel about your a/c but if you take it out. the evaporater sits in front of the radiator . that will free up some air flow
 
I had same problem,not so long ago.These are some of the steps i took,to get rid of it.Remove the AC,that includes evaporator.Make some ducting around FMIC.What i did was, i put piece of sheet metal under and on top of intercooler/nothing on the sides,because is very difficult and not time worthy/.Swap radiators /if you can/.I put Fluidyne. Put two fans on the radiator.One on the inside,one on the outside.Even,if you get rid of the AC,but keep the wires,you'll be able to turn the second fan on by turning AC on,even though you eventually removed it.Last was putting bigger,more powerful fan.On the stock rad i had Perma-cool 14"/which i think is the only 14" that fits on stock rad and is rated at 1650CFM/,but after i put Fluidyne in,with its bigger end tanks,there was no more room for 14"fan.So i turned out again to Perma-cool for theirs 12" high-performance/high-output/ fan rated at astonishing 3000CFM.Since i did all that my coolant temps are between185-198*F,and ocassionally203-205*F,stuck in traffic,but that is with one fan only,plus i see that 203*like for few seconds and then goes down to 195-198/And now is august.If you can not do all that at once,try to get the fan/it cost about $95-99,depends where you get it/ and do some ducting.Good luck,Andy.
 
oh a vented carbon fiber hood even if you paint it will help also because it will giev the hot air somewhere to go and will create good air flow to take the heat out. helps frematicly with under hood temps as well
 
I just took a look and there is less than 1 inch between the fmic and the bottom of the radiator.
There is some wiring in that one inch also. It doesn't look like there is enough space to make any sort of a duct let alone have it be helpful. Is that normal for there to be such a small amount of space when putting a fmic in?
What sort of improvements have people seen from putting like little nostrils in the top of the bumper cover? Would that make a noticeable difference? Would be a little worried that it would also chip all the paint around the cuts I make.
Is seeing temps around 225* dangerous? Or am I still in an ok temp range?
How much of a difference do aftermaket radiators make with the same amount of airflow to them?

I'm not too worried about the fans, cause temps are lower in slow traffic than they are on the highway. The stock fans seem to give more flow than the wind hitting the radiator.
 
I have a FMIC, and in the city I was around 220, but the highway it would find its way up to 230.
Long story short, I got sick of it and just bought a fluidyne rad. Using the stock fan the temp has never gone above 200*. Thats using a 170* thermostat. Its a good piece of mind, and it looks great too.
 
I have a FMIC, and in the city I was around 220, but the highway it would find its way up to 230.
Long story short, I got sick of it and just bought a fluidyne rad. Using the stock fan the temp has never gone above 200*. Thats using a 170* thermostat. Its a good piece of mind, and it looks great too.

Yeah thinking bout that. Would really prefer to not spend 350 bucks now on a new radiator so if there is any other way I can lower the temps that would be better. Just doesn't seem to be much space for the traditional lower scoop thing that people seem to do a lot.
Would like to know the gains people have seen doing the nostril slits in the bumper cover.
 
Lot of people have that problem down here in Arizona. Best fix is to get a set of slim fans that will flow over 1000cfm each. Pro comp has a dealer on eBay that sells them for about $35 a piece. Flows almost 2500cmf combined and so far it has fixed mine and all of my friends overheating problems. We had the exact same problem as well. Stock fans just can't pull enough air over the radiator.
 
Lot of people have that problem down here in Arizona. Best fix is to get a set of slim fans that will flow over 1000cfm each. Pro comp has a dealer on eBay that sells them for about $35 a piece. Flows almost 2500cmf combined and so far it has fixed mine and all of my friends overheating problems. We had the exact same problem as well. Stock fans just can't pull enough air over the radiator.

I thought the fans aren't running at higher speeds? I am not really having as big of a cooling problem while going slowly and in traffic as I am at highway speeds. That is where the temps rise a bit higher.
Also are both fans supposed to turn on at the same time? Only the passenger fan seems to be turning on right now at least when I have checked. Haven't seen the driver side fan going on recently although I believe it was on when I first picked my car up from the shop.
 
Like stated above you need to make some ducting to point the air in the right direction. Now that you have a front mount and no ducting the air is not flowing through the radiator like it used to. All the other stuff like a aluminum radiator and fans work because they compensate for the lack of air flow.
 
The reason you don't overheat in traffic is because there is no air going across the radiator so the fans can pull air across it. At higher speeds the air is hitting the FMIC and not going to the radiator and the fans can't spin fast enough to compensate for the air not hitting the radiator. I have seen it a million times down here. Make sure both fans are working though. With the A/C on both should come on. If either of them aren't working they need to be replaced.
 
Like stated above you need to make some ducting to point the air in the right direction. Now that you have a front mount and no ducting the air is not flowing through the radiator like it used to. All the other stuff like a aluminum radiator and fans work because they compensate for the lack of air flow.

I stated in a couple posts up that there is only like an inch gap or less between the bottom bracket for the radiator and the fmic. There is also some wiring in the middle of the two leaving not really any space for a duct. Is it normal to have such a small amount of space between the two?
 
The reason you don't overheat in traffic is because there is no air going across the radiator so the fans can pull air across it. At higher speeds the air is hitting the FMIC and not going to the radiator and the fans can't spin fast enough to compensate for the air not hitting the radiator. I have seen it a million times down here. Make sure both fans are working though. With the A/C on both should come on. If either of them aren't working they need to be replaced.

Are temps of 225-230* dangerous? Do the fans stay on always if the ac is on? My A/C doesn't work but would the fans still turn of it I put the A/C on?
That must be why only one fan was on, forgot about the A/C needing to be on.
 
230 is getting to the dangerous point. At 222* the car actually shuts the a/c off to take the load off the engine but keeps the fans going. Trying hitting the button to get the a/c fan to come on. Both should come on because they get their signal from the switch.
 
Ok well just turned the AC on(which doesn't work) and my other fan came on. I still have the condensor and everything for the AC but no noise or anything else came on when I turned the AC on. Would that most likely mean my condensor is bad? How much of a difference have people noticed from removing their AC evaporator or whatever it is directly in front of the radiator? If it is removed I'm sure I can easily make a good duct with it gone as that is what is like less than 1 inch away from my fmic, not the radiator itself as I said before.
 
If it was me I would get the a/c fixed. Take it somewhere to get evacuated and recharged with dye in the system so you can find a leak later on. Also make sure you have the belt on :D
 
If it was me I would get the a/c fixed. Take it somewhere to get evacuated and recharged with dye in the system so you can find a leak later on. Also make sure you have the belt on :D

Yeah I still got the belt. Yeah would definitely rather keep the AC but doesn't seem to be much or any space with it there to make a scoop or duct thing to catch air up to the radiator.
Just having both fans going won't help highway overheating will it? The won't stay on all the time right? Maybe the AC one will but if I fix the AC I don't want to have to be robbed of power to cool down a little bit. I think I will just splice in the wiring so that the AC fan comes on when the other one does.
 
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