Overheating Bad Problem
#1
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So a few weeks ago my 1993 1.6 turbo miata with a megasquirt plug n play 2 started overheating very bad. I was hitting 250 degrees on my coolant. I assumed it was a head gasket because I had problems with it before, but I used a sealer and it worked. That was around 6 months ago. So about a week ago I decided to replace the head gasket because I assumed that was my problem. So today I got the car on the ground with the new head gasket and took it for a drive. I was hitting 240 degrees on my coolant and climbing. If anyone knows why my car is still overheating very bad please let me know if you have had similar problems. I have a combustion gas detector so I can check the head gasket but I doubt thats my problem. I used an oem head gasket and sprayed it with copper spray as well. Maybe its because the heater core house is right next to the manifold?? Maybe its because my intercooler pretty much blocks my entire radiator and my secondary fan isn't turning on? I have no idea. Any help would be greatly appreciated. Thank you!!
#2
Cpt. Slow
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Over heating will typically nuke your thermostat, was it replaced? What radiator are you using? What is your bleed procedure? How old is the water pump? Have you pressure tested the coolant system?
#4
Cpt. Slow
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Any oil/grime build up on either side of the crank pulley? VC leaking? Look on the back of the rear timing cover (the metal one behind the cams), is there any oil? These are all signs of requiring cam seals, crank seal, and VC gasket. Great time to replace the water pump, timing belt, idler and tensioner pulleys.
How is your ducting? Is your stock undertray in place? How far from the radiator is the intercooler?
How is your ducting? Is your stock undertray in place? How far from the radiator is the intercooler?
#5
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Any oil/grime build up on either side of the crank pulley? VC leaking? Look on the back of the rear timing cover (the metal one behind the cams), is there any oil? These are all signs of requiring cam seals, crank seal, and VC gasket. Great time to replace the water pump, timing belt, idler and tensioner pulleys.
How is your ducting? Is your stock undertray in place? How far from the radiator is the intercooler?
How is your ducting? Is your stock undertray in place? How far from the radiator is the intercooler?
#10
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Don't let it get that hot. If you're passing 230 and climbing shut the car down. You're going to be stopping soon anyway; better to do it when it's your idea than when the car decides to stop.
Is this a new random issue or did it come after changing something? If its a new issue double check that your fans are working. I've had a fan motor die and a fan relay die, both causing me to overheat at different times. When warming the car up, does it drop a little when it passes your thermostat temp? If no, then the thermostat is likely stuck closed.
Is this a new random issue or did it come after changing something? If its a new issue double check that your fans are working. I've had a fan motor die and a fan relay die, both causing me to overheat at different times. When warming the car up, does it drop a little when it passes your thermostat temp? If no, then the thermostat is likely stuck closed.
#11
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My car was running warm when the intercooler covered the entire mouth of the car. I have ac though. I switched to a taller IC and problems went away. I wasn't seeing temps as high as you. I let it get to 230 once, and that was with ac on. I would get an undertray on the car and block off any places air can be diverted away from the radiator. +1 on making sure your fans are coming on and staying on. I would try having the fan come on earlier and just go ahead and put in a new thermostat, they're cheap.
#12
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My car was running warm when the intercooler covered the entire mouth of the car. I have ac though. I switched to a taller IC and problems went away. I wasn't seeing temps as high as you. I let it get to 230 once, and that was with ac on. I would get an undertray on the car and block off any places air can be diverted away from the radiator. +1 on making sure your fans are coming on and staying on. I would try having the fan come on earlier and just go ahead and put in a new thermostat, they're cheap.
#15
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Update: i took the car out for a short drive yesterday and this morning i just let it get up to operating temp at idle. I look in my radiator. I dont see anything but my overflow tank is filled to the brim. What does this mean!! I had the same problem before i changed the head gasket. If anyone knows why this is happening please let me know!! Thanks
Last edited by jaredfigdor; 07-04-2017 at 11:51 AM.
#16
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With the engine running, grab one of the radiator hoses. Is it rock hard? You could have combustion gases leaking into your coolant system and pressurizing it. Did you check your block and head for straightness when you did your head gasket?
You can also test for this with the engine off. Plug in a compression tester, and pull off the radiator cap. If pressurizing any cylinder makes bubbles come out of the coolant, or pushes up the level, you know you're leaking.
You can also test for this with the engine off. Plug in a compression tester, and pull off the radiator cap. If pressurizing any cylinder makes bubbles come out of the coolant, or pushes up the level, you know you're leaking.
#17
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With the engine running, grab one of the radiator hoses. Is it rock hard? You could have combustion gases leaking into your coolant system and pressurizing it. Did you check your block and head for straightness when you did your head gasket?
You can also test for this with the engine off. Plug in a compression tester, and pull off the radiator cap. If pressurizing any cylinder makes bubbles come out of the coolant, or pushes up the level, you know you're leaking.
You can also test for this with the engine off. Plug in a compression tester, and pull off the radiator cap. If pressurizing any cylinder makes bubbles come out of the coolant, or pushes up the level, you know you're leaking.