Temp rising after the car is off?

[Doward]

I noticed after hard driving (well, boosting up the freeway, then cruising for 40 min @ 80-85mph) when I got off the freeway to get gas, I let her idle for about 45 seconds, shut her off, filled her up - then when I cranked her back up, the temp was up about 3/4 of the way - and promptly came back down.

I figure with no airflow after the motor is off, the coolant is still absorbing more heat from the head/block, but I wanted to verify this is normal. If I let the car sit for about 10-15 min, there is no sign at all of higher-than-normal temps.

Car drove 165 miles today, perfectly great, except for a code 21 + 51 on the way down there, then a 21 on the way back (Gainesville to Lake Panasoffkee and back)

 

[lagged]

not normal. you may have air in the cooling system.

 

[americanjebus]

its normal for it to get heat soak from sitting and boil over, but if your not boiling over after a hard drive and actually overheating than its not normal like lagged said, your thermostat should open and allow the hot water to atleast pour out into the overflow and spill everywhere

do you ever overheat under normal driving?

burp your car to make sure you dont have air in your system, if that doesnt work change out the thermostat and from there get a block tester to check for exhaust emissions in your coolant.

 

[lagged]

its not normal for it to get 3/4 of the way up the gauge.

in theory the temps might rise because the waterpump is nolonger circulating the water.

however, the cause of the heat is the combustion of the engine, so when you turn the motor off what could cause the water temperature to rise? thats right, nothing.

you have an air pocket in your cooling system.

 

[mkIIIman089]

so when you turn the motor off what could cause the water temperature to rise? thats right, nothing.

Erm, when the water stops pumping it is no longer moving through the passages, which are hotter then the water. The water picks up the extra heat becaue it has no where to go any more. Do you have a water temp guage? Have you ever stopped for 10 minutes after warming up the car fully, then looked at the guage when you came back? Its blantantly obvious that there is such a thing as heat soak. I've seen up to 120C in the summer after stopping for a short period of time. (and I have a turbo timer as well)

Now, you should not be seeing the temp guage move as I'm sure its dampened enough to not pick it up.

 

[lagged]

thats what im trying to say. it couldnt be enough to make the needle move 3/4 of the way up.

 

[Doward]

Well, it was 105 degrees out today

Like I said, it was one time ONLY - every other time I have started the car, the coolant was down 3 notches or so, then went back to normal.

Maybe there was some air in there, and it burped itself out. That'd be awful nice of her

 

[lagged]

a properly functioning cooling system should purge out excess air on its own.

 

[IJ.]

Mine Thermo Siphons after it's shut off through the Turbo water jackets you can hear the water moving around!

I guess if I shut it down and watched the temp gauge it'd rise.

 

[johnathan1]

Mine was doing this after any driving (hard or not) it would push coolant out of the overflow after it was shut down, if I didn't let it idle for like a few mins... It turned out to be a combination of a bad fan clutch, and a leak in the gasket around the water pump...