Temp gauge abnormally went past midpoint..a bad sign?

[Deadly BlaZe]

I noticed today after i got into my car and started it up (while engine was fully warmed up already from a freeway drive), the temp gauge needle went a little past mid point. I'm probably just being paranoid but it's never done that before, and we've had hotter weather before. Anyway, i turned the car off right away, and waited a few seconds and started it back up. It went past the mid point again, but then went back to the middle again and stayed there. I'm just worried if this is some sort of sign of a head gasket going bad or what. Any insight would be appreciated.

 

[silver bullit]

Check your coolant level and condition.

 

[eclipsegst1990]

I didn't check your mods, but if this is an aftermarket gauge, depending on where you installed the unit, you may be observing the thermostat opening and closing which is affecting the coolant reading. My gauge does this sometimes and it is really nice to see the stock gauge reading a relaively steady temperature while my aftermarket shows whether the thermostat is working properly.

Also, check your coolant level and bleed the system if necessary (my 89 Galant had a bleeder screw on top of the thermostat housing). Furthermore, it could be time for a new thermostat and replacing it now might be good "piece of mind."

 

[Defiant]

I noticed today after i got into my car and started it up (while engine was fully warmed up already from a freeway drive),

Sounds like soak. Did it come back down right away?

 

[cool_g_83]

Did it overheat while on the freeway? If not, then your radiator might not be seeing enough air, which would explain the overheat AFTER the highway drive (assuming this occured in stop and go traffic). Do you have both radiator fans in? Are they working/coming on?

 

[Deadly BlaZe]

Sounds like soak. Did it come back down right away?

Well, yes it did come back down right away. And did not happen again while I was driving, so it only went past the midpoint at idle.

I didn't check your mods, but if this is an aftermarket gauge, depending on where you installed the unit, you may be observing the thermostat opening and closing which is affecting the coolant reading. My gauge does this sometimes and it is really nice to see the stock gauge reading a relaively steady temperature while my aftermarket shows whether the thermostat is working properly.

Also, check your coolant level and bleed the system if necessary (my 89 Galant had a bleeder screw on top of the thermostat housing). Furthermore, it could be time for a new thermostat and replacing it now might be good "piece of mind."

I just flushed out the coolant a couple months ago and topped it off. But I guess it wouldn't hurt to check it again. And no i don't have an aftermarket temp gauge. The stock one has been pretty reliable (one time i forgot to screw the radiator cap back on and the temp guage helped me realize it before it completely over heated.)

Also, I was wondering, is it bad to drive on the freeway often with these cars? I mean 5th gear, 70 - 80 mph, 3k-3.6k rpms every day doesn't sound very good.

 

[420aStonerBlock]

Freeway miles are fine on your engine. Our engines are made to handle 7500 to 8000ish rpms from the factory. Running 4k all day wont do anything to our engines. It may wear on your engine but actual damage usually does not occur unless you are close to redlining, massive amounts of boost, wide open throttle, etc. I would rather run around 4k for a few hours then to be driving around in the city, because there is less load on the engine if your are cruising at a constant speed.

 

[Deadly BlaZe]

Did it overheat while on the freeway? If not, then your radiator might not be seeing enough air, which would explain the overheat AFTER the highway drive (assuming this occured in stop and go traffic). Do you have both radiator fans in? Are they working/coming on?

Both radiator fans are working, that's the first thing I checked for. And I checked the coolant level just now, and it's full.

One thing I forgot to mention, I could've sworn i saw smoke coming out from under the hood when the needle went past the mid point after i turned it off the first time. I thought maybe some coolant spilled in the engine bay some how and that's what was burning, but i opened the hood and there was no smoke or anything leaking. Strange.

 

[Defiant]

It may just be that you'd not noticed it before. When a hot engine is shut off, you'll have a rise in coolant temperature as the flow is no longer boosted by the water pump. Thermosiphon will keep this from becoming a damaging condition, and the rise will not be enough to bother an engine with a healthy cooling system.

 

[DroopYeyeS]

You said at highway speed temp is fine, but at idle it starts to rise. Then you think you saw smoke? Was the smoke toward the driver side? Look at the timing cover and/or oil pan on the driver side, and inspect for signs of coolant. If coolant is present, I'd look at getting a new water pump. Thermostats usually don't slowly fail. Typically their either stuck open or closed. Althought if you do the pump, I'd do the t-stat at the same time.

 

[wcpierson]

Did you just turn the car off after getting off the highway or did you let it sit for a minute or 2 before shutting it off? Do you have a turbo timer? The fans werent running while you were on the highway because your radiator was being cooled enough by the flowing air. If you shut your car off before the fans had time to run for a minute or 2 the temperature of the coolant will rise because it is no longer receiving the airflow you were seeing on the highway. Always turbo time your car or let it idle for 2-3 minutes before shutting it off.

 

[IQuikSilvaI]

yeah even if your car is overheating NEVER just turn it off and let it sit. as he said the coolant temperature will rise even higher. and i am sre your turbo did like it either

 

[Deadly BlaZe]

Well i've always let the car sit for a minute or 2 after a long drive, it was just that one time where I was in a hurry to get to the bank before it closed, that's when i hopped back in the car 2 minutes later, started it up, could've sworn i saw smoke coming from the passenger side, and temp gauge went past mid point.

But, it hasn't happened yesterday or today. So maybe it was because i shut it off abruptly before letting it cool down. I'll be sure not to do that again.

 

[brandonzero0]

i've said this a few times but some times when you flush your coolant and put new coolant in theres and air bubble and you need to run it out alot of my cars heated up alot and kept fluctuating between midpoint and all the way up, i filled up the overflow and let it run itself out but let it sit between driving periods and it went away in no time.

 

[PIMking]

sorry to bring a dead thread to life but if you open the thermostat (before you install it) and put an advil in it to keep it open then install it fill with coolant you wont get air bubbles and fill it up right away the first time. plus the advil will dissolve and wont hurt the car at all!