my temperature gauge will be fine right in the middle then it will go op to hot fast for like 10-30 seconds sometimes then drop right back down to normal.. i have burped the system and got a good amount of air out of it.. i thought it was fine.. where could air be coming from to get back in it.. and its random..i can drive it on the main highways for hrs and it wont move then ill randomly go to the store the next day and it will start jumping all around.. Or also could it be my thermostat getting stuck closed..? it just getting really annoying because i put a new headgasket and all in it and dont feel like frying something. its an 88 turbo supra.
temp problem
- Thread starter s7mgte
- Start date
s7mgte;973294 said:
Ah sry I just saw that. No i didnt have much air if any really in my system at all. However since thermostats are supposed to break OPEN now then im not sure. It might veery well be a loose connection. Next time it happens pull over to the side, leave your car running and open the hood. See if there are any steam appearing from any connections or look on the ground with your car running and see if there is any fluid leaking.
Mine does the same thing, but when I tap the plastic in front of the temp gauge it goes back down. Try it the next time it spikes. If it goes back down after a healthy smack then it's a bad solder joint in the gauge area. I've just been too lazy to pull the dash apart to fix mine.
Mine also wnaders randomly. Ill be going down the road at operating temp, get on it a little bit, neddle goes up, tap the guage cluster and it goes back down, also by turning the heat on and it goes down. I was thinking air in my system, the thermostat or a lose conection.
I just find it funny that we have all these "me too!" posts and yet not one of them gets the hint.
Ah that's right, that's the loose connection gauge!! DOH!!
Personally, I'd run a block test before a pressure test. Just because I've had BHG's go undetected by a 15psi cooling system pressure test. But if you think I'm FOS then at least listen to the guy with the orange name.
Ah that's right, that's the loose connection gauge!! DOH!!
Personally, I'd run a block test before a pressure test. Just because I've had BHG's go undetected by a 15psi cooling system pressure test. But if you think I'm FOS then at least listen to the guy with the orange name.
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First change the thermo. I had one close shut once. Personally I don't think your thermo would work and not work from highway to city driving but it will take you 10 minutes to eliminate one variable.
Than start from the worst case scenario to the least.
While your burping the system and bringing the car up to normal temp start your block test for a BHG. If that passes bend on one knee and give thanks to the Almighty.
Do a pressure system test. Now you have eliminated any leaks.
If that passes check your fan clutch. Your fan draws air through the rad and keeps your car cool in city driving or idle when your not on the highway pushing air though the rad. If your temp does go up and your auxiliary fans kick in and the temp drops that could tell you your fan clutch going on the fritz.
Find a second method to test temp of the coolant. Variations in temp with your second method would verify that you gauge is being true to you.
The old saying "The gauge must be wrong" has cost allot of people money and heartache. The gauge is wrong or a loose wire should be you last best guess.
I am new to the supra scene so if I have made any mistakes please correct me. No flaming plz.
Than start from the worst case scenario to the least.
While your burping the system and bringing the car up to normal temp start your block test for a BHG. If that passes bend on one knee and give thanks to the Almighty.
Do a pressure system test. Now you have eliminated any leaks.
If that passes check your fan clutch. Your fan draws air through the rad and keeps your car cool in city driving or idle when your not on the highway pushing air though the rad. If your temp does go up and your auxiliary fans kick in and the temp drops that could tell you your fan clutch going on the fritz.
Find a second method to test temp of the coolant. Variations in temp with your second method would verify that you gauge is being true to you.
The old saying "The gauge must be wrong" has cost allot of people money and heartache. The gauge is wrong or a loose wire should be you last best guess.
I am new to the supra scene so if I have made any mistakes please correct me. No flaming plz.
gtsfirefighter
SM Expert on White trash
s7mgte;973883 said:
Huh?
It's been doing this ever since you replaced the headgasket or ever since you've had the car?????
did you get the block decked and checked for smoothness ?
did you get the head milled ?
that MHG is worthless if you dont do both of those things, if you did not you are lucky you got 600 miles out of it
did you get the head milled ?
that MHG is worthless if you dont do both of those things, if you did not you are lucky you got 600 miles out of it
i got the head milled and ive heard you dont need the block milled being that it usually doesnt get warped. so i left that alone. i got to bleed to system properly i think.. i changed the thermostat today and the temp did the same thing. also i taped the gauge and it still didnt change so i know its not those 2 things.. has to be more air in system.ATL88Supra;973978 said:
dude you ALWAYS Deck the block, there is no room for error on the 7mgte if you used a MHG and DID NOT deck the Block then you just wasted money and time, it wont suprise me at all if you are blown
and who ever said that you did not have to deck it was a goddamn fucking moron
and who ever said that you did not have to deck it was a goddamn fucking moron
ATL88Supra;975970 said:
well ive heard it from mechanics too.. reason being the head is aluminum and the block is cast iron. also im not sure if this matters but i thought my heater core was going so i just bypassed it with a hose and a few adapters. Figured id add that in in case it matters. and also if i blown.. dont you think i would see coolant in my oil and lose boost and all kinds of other things?
its not about warpage, its about smoothness, the mateing needs to be PERFECT thats why you deck the block....................... and if they did say that they dont know how to work on a import motor,
its most likely blowing air in to the water jacket there for pushing the coolent out and filling the system with air
its most likely blowing air in to the water jacket there for pushing the coolent out and filling the system with air