i was driving to school the other day with out my coolant overflow (i had it capped off) and when waiting in line to get gas i noticed my temp was almost in the red i drove it across the street where i could park it and let it cool down when it cooled i went to add more coolant (was running a little low cause i ran out after putting the motor back in... ) anyway i added more coolant and went to start the car and it now runs like crap... the whole car shakes almost like running it without the maf plugged in

so i got the car towed home and the radiator hose was sucked in and agian i tried to start it but the same thing happened

i think the car overhaeated due to not enough coolant in it but now did i blow a headgasket? i checked the oil it doesnt look mixed i checked the coolant and it has some brown in it but it looks like its just dirty i havent gotten to test the car sense it happend to see if it would overheat agian because im afraid to drive it with the way its running

crfridah said:

i was driving to school the other day with out my coolant overflow (i had it capped off) and when waiting in line to get gas i noticed my temp was almost in the red i drove it across the street where i could park it and let it cool down when it cooled i went to add more coolant (was running a little low cause i ran out after putting the motor back in... ) anyway i added more coolant and went to start the car and it now runs like crap... the whole car shakes almost like running it without the maf plugged in

so i got the car towed home and the radiator hose was sucked in and agian i tried to start it but the same thing happened

i think the car overhaeated due to not enough coolant in it but now did i blow a headgasket? i checked the oil it doesnt look mixed i checked the coolant and it has some brown in it but it looks like its just dirty i havent gotten to test the car sense it happend to see if it would overheat agian because im afraid to drive it with the way its running

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Change the thermostat first, fill with coolant, and see if its gonna suck the hose again. also if ## hose is old and soft , you need to replace it.

Check the radiator cap, they tend to get dry rotted and let coolant leak out.

Alright I'll try both of those things today do you guys thing that the rough running has anything to do with it overheating cause I'm just trying to find out whatscwrong before I go ahead and take the head off to replace the gasket

crfridah said:

i was driving to school the other day with out my coolant overflow (i had it capped off)

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You can't seal a pressurized cooling system 100%. Once the temperature gets to the boiling point, steam (pressure) pockets are produced and the coolant stops moving. Now in a normal system, the steam is circulated to the highest point (the rad cap) where it's harmlessly vented into the recovery tank.

Your genius idea of capping off the system entirely prevented coolant from being able to move, so the engine just gets hotter and hotter...compounding the problem until something gives (usually the gasket).

crfridah said:

i added more coolant and went to start the car and it now runs like crap... the whole car shakes almost like running it without the maf plugged in

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You overheated it, warped the head, and blew the gasket between cylinders 2&3 because you prevented pressure from escaping the cooling system. Good luck.

crfridah said:

car and it now runs like crap... the whole car shakes almost like running it without the maf plugged in

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Damn ive must a miss that part ....

Like JusMX141 , you will need head gasket job, and head resurfaced, if you lucky enough , if you oil temps were hot enough ... your engine bearings might have gone bad too.

I'd be more concerned about distorted cylinder walls and cracked ring lands than any bearing damage- I guess it depends whether any coolant made it into the oil or not, but it's not likely that any bearing damage occurred during a short trip.

Is it leaking coolant? Did you check under your car and see any leaking coolant? Same thing used to happen to me. I had the oem radiator and it had cracked on the bottom. My car kept on overheating and burning oil. I replaced my radiator with an aluminum radiator. It stopped the overheating issue. For the burning oil, I replaced it with a heavier weight. I was using Royal Purple 10w 30 but kept burning. So I switched over to Valvaline Vr1 Racing oil 20w 50. Car runs great now and doesn't burn oil.

dump the oil, look for coolant in the oil. Sounds like a blown HG. Replacing it isnt that hard. Buy a cam gear block and it will make life much easier.

my 99 eclipse gsx has been having alot of problems overheating! Me and my dad replaced the thermostat, heater core, water pump, new radiator, coolant and its still over heating! We just got the new water pump on about two days ago. I took the car for about a 20 min ride and everything was good. Then when i drove it home (about 45min drive) i noticed the temp gauge went the whole way up. I stopped at the gas station to let it cool down and when i popped the hood it was smoking around the overflow and the coolant over flow cap was popped off and it sounded like the coolant in the overflow was boiling? Not sure if theres still a leak somewhere and the coolant is leaking out or if the head gasket needs replaced. Finally got the car back to my apartment, going to check the coolant and everything in the morning. Any suggestions on what else it could be?
thanks alot!

Could be a head gasket. You can rent a pressure tester from most parts stores to help narrow down the culprit. A leak anywhere can make the car overheat. Also can check the spark plugs for coolant spotting.

do you know of any tips or tricks, or as to whats the best way to check for leaks?

The purchase, or rental of a coolant pressure tester.

Something such as this. Also, pull the plugs out of it. A good firing engine will turn the plugs a nice white-brownish-tan color on the ceramic. It should look like a freshly roasted marshmallow. Coolant presence will make little black spots appear on the ceramic.

Have you checked/replaced the radiator cap? That can cause coolant to bubble and flow into the overflow. What percentage mix of coolant are you using? These cars run pretty hot, so it would be best to use 70% distilled water and 30% coolant. Unless your car will see temperatures below 0*, then you should use a 60/40 mix. But generally, 50/50 is too thick.

Have you verified the new thermostat isn't stuck? I've seen dozens of new thermostats fail right out of the box, especially the cheap parts store brands. This is easy to check, just feel the lower radiator hose once the car is warmed up. If it's cold, the thermostat is bad.

Do you have both original cooling fans? Can you hear them running at any point?

If all that checks out, you should run a pressure test of the cooling system and/or the cylinders. Like Talonalex showed, there is a coolant pressure test that you can buy or rent from auto parts stores. You can also purchase a chemical testing kit that will show if combustion gasses have been entering the cooling system. But IMO, the best way to test the head gasket is through a cylinder leak-down test, which is described here: http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

Definitely going to be the head gasket I'm assuming from what it sounds like I had the same problem
last summer in my 1gb talon boiling overflow tank and was going through coolant like a boss, it was the
head gasket never had a problem after.

I have a 1998 eclipse gst that is getting hot on me. The car has 125,000 miles on in and at 108,000 I did timing belt, heather core, and water pump. I just put in a new rad, thermostat, and water temp switch. The other day the car started getting hot on me someone put stop leak in at some point but I thought I got it all out. I have flushed and flushed the cooling system and even ran an open thermo. It is still getting hot I am thinking there is a clog somewhere but idk. Any advise would help. Thank you

And fans are coming on.

if your running w/o a thermostat and it's still getting hot, I hate to say it but there is probably no flow which means that the water pump you put in could be bad..... always use OEM water pumps, pretty much all others are junk. have you checked your oil for coolant or are you losing any coolant?

The OP is my son. I just wanted to add a little more info. We are going to get the car back to my garage then will rent a coolant pressure tester to be sure. The head gasket was replaced by a mechanic about a year ago but the car hasn't even been driven a thousand miles since then. But, we will make sure to do the pressure test to take the guess work out of it.

The radiatior cap is new but will replace that also just to be sure.

The coolant we used was a straight 50/50 mix. The car goes north to the Pittsburgh area when running well so we may switch it up to a 60/40? It will see a lot of cold temps in the winter.

I put this thermostat in and simply got it from Napa. Any suggestions on a better place to get one and it's not that expensive to replace so we can put a new one in again to be sure and check the hose like suggested.

Cooling fans are not original but came from another wrecked eclipse. They do run so I think we are okay there.

Thanks for the help!

.....and will pull the plugs to check also.

When the car comes up to operating temp see if the upper and lower radiator hoses both feel warm or if one is cold. I have seen thermostats bad out of the box FYI.

Pull the plugs and pressure test when car is cold look for signs of coolant in the cylinders . I also use a leak down tester and while putting air pressure in cylinder watch the coolant and if the level starts to rise then that cylinder is sucking in the fluid and burning it .

TG924 said:

The OP is my son. I just wanted to add a little more info. We are going to get the car back to my garage then will rent a coolant pressure tester to be sure. The head gasket was replaced by a mechanic about a year ago but the car hasn't even been driven a thousand miles since then. But, we will make sure to do the pressure test to take the guess work out of it.

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Why was the HG replaced? If the car overheated before, the head surface could be warped causing a bad seal between cylinders or etc.

TG924 said:

The coolant we used was a straight 50/50 mix. The car goes north to the Pittsburgh area when running well so we may switch it up to a 60/40? It will see a lot of cold temps in the winter.

I put this thermostat in and simply got it from Napa. Any suggestions on a better place to get one and it's not that expensive to replace so we can put a new one in again to be sure and check the hose like suggested.

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Try 60/40 & look into a Stant thermostat (Part # 14077) at AdvanceAuto

TG924 said:

Cooling fans are not original but came from another wrecked eclipse. They do run so I think we are okay there.

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These could contribute to the problem since many off/ebay brand fans don't push as much air (cfm) as stock fans. Good luck

Since my last post was deleted somehow I will try again. I noticed when I have changed a heater core if the system isnt bleed properly it can lead to overheating. You said you just changed the heater core and numerous other items. I have always found that when I do a heater core I will use a water filler. It basically allows you to pressurize the system while still adding water I will look for the part number its made by lisle. I will attach the adapter fill with antifreeze, water, wetter water, be cool, whatever it is you use and also have the heater on hot turned up all the way any vent dont matter I will gurantee there is air in the system. You will noticed it releasing the air. I had this happen 2 times thats how I know. I also agree with the thermostat idea cause that can be a main issue. If i ever doubt my thermostat I simply remove it to see if th car is still having the issue if not you know its bad if it works at least you can check one off your list.

The boiling in the overflow just and cap popping off are classic head gasket symptoms. Ever do a compression test? Whats the oil look like, milkshake or normal?
As for the fans get the Mishimoto slim 12'' fans. Easy to install, and work great. Also look into a 180 degree thermostat for cooler running temps.
When you replace the Head gasket get both surfaces resurfaced and dont go with an oem gasket, get a multi-layer gasket and pick up arp head studs, the head gasket probably wont be an issue ever again.

A mix of 60% water and 40% coolant will freeze at about -14. So if there's any chance the car will see temps anywhere near there, it would still be best to use 50/50. More water is just better for cooling, so my "too thick" statement was for the majority who don't need -30* protection.

In my experience, parts store thermostats are truly hit or miss. And even if they work when installed, it's not uncommon for them to randomly seize up. The only parts store brand I would suggest is Fail-Safe from Oreilly. But a Mitsubishi thermostat would be the best option and cheaper. Either way, it's not urgent to replace it unless the lower hose is cold.
Link to Mitsu part:STM: OEM MITSUBISHI THERMOSTAT | 95-99 DSM | MD315301

After car is heated up, when you pop the radiator cap off while the car is running, do you see any tiny white bubbles coming up to the top?