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Car Overheated / Overheating / Overheats [MERGED]

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NTRCOOL

Probationary Member
24
0
Apr 10, 2002
Richmond_Va.
OVERHEATING? The issues and their solutions have remained the same- either you don't have enough cool air reaching the rad, there's a cooling system obstruction which is preventing coolant from circulating, or your head gasket has failed and is allowing coolant to be consumed or pushed away from the engine.

Discuss all possible overheating problems and solutions here.



OK,
I just left my house to go over to my GF's,and happen to look down and see my needle right before the red mark. This just happened out of nowhere. I stop the car as quickly as i can, and pour in some coolant(Coolant a little low). Still same thing. Welp im in the middle of the road, and HAD to get it home. Im only 5 min from my house. I decided to try and make it(I really had no other choice). Welp I drive no faster than 20mph, and the temp needle is BARELY into the red the whole way.And occasionaly to the left of it. Am I ok?? Do ya think any damage was done?? And im thinking either thermostat, or water pump. For each of those, whats a round about $$ figure to get replaced?? Any info you have would be GREATLY appreciated!
 
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Do you have a 1g or 2g thermostat housing. this is probably the cause of your problems finding the right thermostat. post a pic up here.
 
for some reason i can't find a thermostat that fits good in my 97 eclipse with a 6bolt swap. i tried one from a 93 and a 95 and a 97. for some reason the maintenece book says that the thermostat goes in the side of the engine but mine goes on the housing that the radiator cap is connected too. this is my first dsm with 6 bolt swap need some advice

If you have a 6 bolt swap, you have to use one from a 90 or 91...92 and up have 7 bolt engines....and yes, it goes in the part that patrudes from the engine just below and behind the radiator cap.
 
heres a photo
 

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that is where the thermostat goes. i took that housing off and it is just a small port for water that comes from the engine, no room for a thermostat

the one i got for a 90 91 had a rubber gasket that make the housing not fit. do you just take off that rubber gasket
 
You took off the wrong part. You took off the upper rad hose outlet and that is not where the thermostat goes. Follow the lower rad hose up to a 2 bolt flange, take that one off and thats where your thermostat is....

Not on a 6 bolt... the thermostat goes right where the red looking round hole is. It has a slot and just has to use a little rtv on it and does not even need the gasket....unless it is not an actual 6bolt. Looking at my laser right now and that is where it goes on it and it has a 6bolt. It bolts down and the top has a diverter that curves to start where the radiator hose attaches to.
 
Ok, so my car overheated about a week and a half ago and popped the smaller hose on top. No big deal, low on coolant, my fault for not knowing the Rad symbol on the cluster LOL (only owned the car a month or so). I replaced the hose and added coolant, ran fine for a week. I did a flush with 50/50 and a 160* Tstat and it has Very good looking synthetic oil in it. No issues for almost another week. Well it's running hot again. When i replaced the hose, I was at my local speed shop and the owner was also a DSMer and noticed that my Rad fans were both connected to my A/C unit, only running when my A/C was. Is this normal? I'll wire in a toggle if i have to haha. Also, Aluminum Rad, clean fluid from what i could see when i flushed it.

So, new Tstat/coolant, freash synthetic, both fans running constantly, A/C also on. Still overheats Randomly. :banghead: Any Ideas?
I'm not sure yet if I am losing fluid as only when it's overheated have I had to add any, but I haven't left any puddles at work.
 
Randomly overheating not leaving puddles and having to add time to inspect the headgasket. Sometimes they are not so obvious to spot. First start with a thorough coolant system check pressure test it then go from there.
 
When i replaced the hose, I was at my local speed shop and the owner was also a DSMer and noticed that my Rad fans were both connected to my A/C unit, only running when my A/C was. Is this normal?

No that's not normal at all, and would cause overheating when idle / sitting at lights / etc. One of the fans should kick on when it gets hot, the other should be your AC fan.

I'd let the car warm up and and just watch the fans, if one of them never kicks on, then that's where I'd start.
 
I had some similar issues recently. I had a broken wire to my radiator fan switch. This is essentially a coolant temp sensor that only controls the fan. It is set to turn on the fans at about 190*. Turning on the AC switch in the cabin, even without a compressor or gas in the system will command both fans on no matter what.

Short version, I would check out the wiring to the fan switch, which is located in the thermostat housing. If your wires are intact, check continuity of the switch when at temp. The temp gauge should be a little to the left (like 10*) of the coolant symbol on the gauge when the fans come on. If you don't get a closed circuit by the time its on the other side of the symbol. Turn it off, and get a ride to the auto parts store, because that switch needs to be replaced.

Good luck! :dsm: :talon:

Edit: sorry OP just read the last two sentences of your post, I'm going to agree with Brian on a head gasket. Do you still have a belt on your AC compressor? If the AC is actually loading the engine, its hurting more than helping you.
 
Make sure there are air pockets in the cooling system. I have seen some random things from air pockets.
 
More than likely, it is the head as stated due to lift or a bad bolt/stud. I will say that running a 160 degree thermostat in Alabama during the summer is a bad idea. Once the car warms up, unless you have a triple core radiator with fans from a J-79 engine, the coolant is going to always be flowing as your thermostat is going to be wide open all the time.

This means that the fluid never stays in the radiator long enough to cool off enough to keep the head/motor cool.

If you have an aftermarket turbo mani that has no shield, that will contribute to the problem as well. If you turn on the A/C and put it on heat, that will help cool the coolant by using the heater core as a radiator and forcing on the other fan. Make sure your fans are wired up as they should be or wired to be on all the time. The A/C fan should come on when the A/C is on and the other fan is supposed to come on a around 190.

If you have slim fans, be sure they are not the cheap ones that flow only 700cfm as the stock fans are rated around 1300 and that makes a big difference too when at low speed or sitting still.
 
Load from the A/C is a for sure, RPMs drop when its on and the car sounds like it's about to die when the RPMs drop after going to neutral. The aluminum rad looks big to me but I never compared to stock since I did not install it, but the 180* Tstat makes sense, the 160 was recommended to me by someone with a lot more expierence than me so I went with it. As for the HG, it's one of those "afraid to look under the bed" things LOL but yes I will get it up to temp and and inspect it as best I can, any bad spots? I know on my old 4runner 3.slow, it wsa the #5 cylinder area that went bad most ofter on them.
Fans are stock from what i can tell.
I think I may just re-wire the fans on a toggle or the ignition, and remove th A/C all together. I rarely use it anyway, windows down, system up haha
 
Ok, so after more observations, the fan seems to be kicking in at what I assume is 190*. Also there is a light drip coming from the rad drain plug so I'm sure under pressure when running, it loses a good amount which contributes to the random over heating. I'm going to replace the gasket but the rad isn't stock so I'm not sure how to go about getting another gasket... Are they all one standard size?
I had it running and looked over the HG as well as I could with a flash light and couldn't see anything wrong, no smoke or oil or coolant. So I'm hoping all is well. Any other ways to check?

I think I'm meant to own a DSM LOL These issues I keep getting don't bother me a bit. I kind of enjoy learning the car more before I get into the go fast stuff. Is that wierd?
 
Short version, I would check out the wiring to the fan switch, which is located in the thermostat housing. If your wires are intact, check continuity of the switch when at temp. The temp gauge should be a little to the left (like 10*) of the coolant symbol on the gauge when the fans come on. If you don't get a closed circuit by the time its on the other side of the symbol. Turn it off, and get a ride to the auto parts store, because that switch needs to be replaced.

The fan sensor is located at the bottom of the radiator on the passenger side.

Pull the plug on the sensor, and connect both wires together by inserting a paper clip or piece of wire into each side of the plug. With the ignition key on and the plug shorted, the fan should kick on. If the fan kicks on, the sensor is bad. If it doesn't come on, check the fan relay in the fuse box by the air filter.

But...

If you are still overheating with both fans running, you have other issues. Did you burp the system when you added/replaced the coolant?
 
If it was a hg it would not cool down. It would get hotter and hotter while running. Also you would see temps 250degrees.

I was really doubting the HG, no smoke, runs strong with full coolant LOL clean oil. It's gotta just be a leak, I'm at work so I can't do much at the moment but I'll get a better O-ring for the drain plug and also I was using a gasket on the Tstat housing, not exactly the best seal when the temp rises but it came with the Tstat so I put it in. I'll get some of the orage goop crap. RTG? I can't remember what it's called LOL Once i fix this and my injector seals FINALY come in, I'll have a reliable DSM once again LOL then I'll start hunting for a socketed EPROM ECU. Maybe swap my wheels with someone I don't know yet.

Anyways LOL Thanks for the advice. I know I post a lot like a noob but I want to be very sure and fix things right.
 
Ok so I was overheating the other day. I replaced thermostat, and still nothing. Next I did a coolant flush and that didn't help either. So then I replaced my rad cap and it helped a little with overheating but it made my upper radiator hose swell up and get rock hard. Is it a faulty cap or what? It still overheats in traffic but never at a steady pace. Also sometimes it seems like it goes down/up when I go around a sharp turn or get on the brakes. Any insite will be greatly appriciated! Thanks
 
Does your fans turn on? When it is over heating is there a noticeable difference in temp between the top and bottom hose? Have you been losing any coolant?
I don't lose any coolant. Both the upper and lower hose both get hot. And fan turns on at correct temp. Not exactly sure what it could be unless I got a bad cap or if the old cap was bad then put the new cap on and system wasn't used to the pressure so the upper hose may have been weak and just bloated. I don't know though..

Also I did a compression test just to rule out a head gasket falure. I figured it wasn't because it was replaced not too long ago.
 
So you think its just the hose? But would that let it overheat?

It would collapse in on it self, thus not allowing coolant to flow properly. Probably 9 times out of ten if you would hit the gas it probably suck in on it self causing a blockage.
 
How fast does the temperature fluctuate? Fast enough, it could mean your low on coolant and coolant is not contacting the sensor in thermostat housing...

Do you have a huge FMIC with no ducting? If no FMIC, how does the A/C condensor fins look? I spent a good amount of time straightening out the fins putting my car back together
 
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