Overheating Issue

[nimdivino]

Hello,
So last night I left my car idling and when I got back (maybe 10-15 mins) the temp was almost to the red zone... I then moved it real quick to park but I noticed as soon as I moved, the temperature went down and by the time I get to the stop sign, it went back to normal. I thought this was very wierd.

Any thoughts? I'm going to let the car idle tonight and check the fan to see if it turns on.

Thank you

niM

 

[goldNSX]

Check the radiator coolant hoses for equal temperature. If they're not and you run in the red replace the thermostat.

 

[nimdivino]

Thank you.. I'll try that tonight..

Though I hope its not the thermostat because we just changed that.


niM

 

[Sulley]

How's the coolant level.

 

[Briank]

If you changed the stat did you fully bleed the system?

 

[RON98]

Happened to me a long time ago in my old nsx.

Drive through window, started getting hot. I had to rev the motor to keep the temps down.

check your front fans and relays first since you don't need to remove anything like the thermostat. They should turn on the fan when your radiator gets hot. You can also feel the radiator hose to see if the outlet from the engine is warm once the car heats up.

If the radiator is hot, your car is over heating then its probably a fan issue where its not turning on when it should.

 

[nimdivino]

If you changed the stat did you fully bleed the system?

I thought maybe there's air in the system. I haven't asked my friend if he bled the system though. I'll find out more tonight.

Thanks guys.

niM

 

[nimdivino]

Happened to me a long time ago in my old nsx.

Drive through window, started getting hot. I had to rev the motor to keep the temps down.

check your front fans and relays first since you don't need to remove anything like the thermostat. They should turn on the fan when your radiator gets hot. You can also feel the radiator hose to see if the outlet from the engine is warm once the car heats up.

If the radiator is hot, your car is over heating then its probably a fan issue where its not turning on when it should.

That's on my number 1 to check for tonight. What I don't get though is why does the temp go down if you rev the motor?

Thank you

niM

 

[RON98]

That's on my number 1 to check for tonight. What I don't get though is why does the temp go down if you rev the motor?

Thank you

niM

if you rev the motor, the water pump increases flow and moves the coolant along bring in new coolant from the radiator.

It also happens when your coolant is LOW. you'll be able to rev your motor, increase circulation and cool down the motor.

so if your reved your car and the car cooled down, your thermostat is probably not the culprit. Because if the stat was closed, you can rev it till the cows come home, it wont make a difference. Check coolant level also.

 

[nimdivino]

Great info RON98. Thanks so much.

niM

 

[RON98]

Np

the nsx cooling system does a great job self bleeding.

usually you wont have problems if you don't drain the system completely.

just make sure your coolant is full. if it is full i would check fan.

 

[nsxotic911]

I have found that if the system is not bled properly, the wat may not even make it TO the radiator and the fan won't even turn ON because the sensor isn't switched.

Bleed your system EXACTLY as the manual says. Have someone that has done it do it, not someone that normally works on the Civic and hits one of the bleeder valves.

The order is so critical.

 

[RON98]

congrats on trouble shooting! :biggrin:

 

[nimdivino]

So I checked the coolant reservoir and it was very low. I think that was the main reason. Filled it up with Acura coolant, let it idle for about 15 minutes, drove it for like half-hour, and let it idle again for 5 and it didn't even get to the normal operating temp. (it was a line under normal temp). I waited for the fan to turn on but it never did.

So I guess its back to normal. I'm a little paranoid with my fan though but it should be alright. It was just cold yesterday and I'm sure that was the reason.

Again, thank you very much for all your help..

niM

 

[nsxotic911]

So I checked the coolant reservoir and it was very low. I think that was the main reason. Filled it up with Acura coolant, let it idle for about 15 minutes, drove it for like half-hour, and let it idle again for 5 and it didn't even get to the normal operating temp. (it was a line under normal temp). I waited for the fan to turn on but it never did.

So I guess its back to normal. I'm a little paranoid with my fan though but it should be alright. It was just cold yesterday and I'm sure that was the reason.

Again, thank you very much for all your help..

niM

To be absolutely sure, I'd wait for the fan to turn on, and if it doesn't after 30 minutes of idling + revving to 3000 rpm in neutral, I'd do more troubleshooting.

Otherwise, 45 minuets later on the freeway, the car will overheat again.

I'd suggest you do some compression test to make sure the headgasket isn't leaking etc... to be safe..

 

[RON98]

So I checked the coolant reservoir and it was very low. I think that was the main reason. Filled it up with Acura coolant, let it idle for about 15 minutes, drove it for like half-hour, and let it idle again for 5 and it didn't even get to the normal operating temp. (it was a line under normal temp). I waited for the fan to turn on but it never did.

So I guess its back to normal. I'm a little paranoid with my fan though but it should be alright. It was just cold yesterday and I'm sure that was the reason.

Again, thank you very much for all your help..

niM

fill her up, go drive her around and watch your water temp.

the small amount of air in the system will work its way out.

 

[nimdivino]

Last friday, I checked the coolant again. I lost a tiny bit but nothing to be worried about. I filled her up and drove her hard to the smog station (to warm up the cats) I had to wait a little bit so I left the engine running and watched the temp gauge. When it was ready for the actual test, I revved the engine 3500 for about 4mins monitoring the temp. My gauge never went to normal, it was always a line below normal. Checked the fan and it was running.

I checked the coolant again the next day and I didn't loose any. whoohoo. No more overheating and I passed SMOG.

Thanks again RON98

niM

 

[RON98]

np :wink: