PLEASE HELP! overheating mystery!!
Thread Starter
Joined: Apr 2010
Posts: 15
From: Canada
PLEASE HELP! overheating mystery!!
This is a long story so bear with me. I am at my wits end and even cried in frustration a couple days ago.
The problem first started when I was getting no heat in my 2001 V6. We had the thermostat replaced, the heat worked for a bit, but then engine started to overheat. So we took it into Ford, they bled an air lock out, and car stopped overheating. Then we found some coolant leaks, so we replaced the thermostat again, replaced the top rad hose, and was still leaking. We then found out it was a crack in the water pump so we replaced that last week. Now there's no leaks, BUT it's overheating again!!! So we brought it back, they bled another air lock out, and did a head gasket check. No leaks coming from anywhere, seemed like it was just another air lock. But nope, today it starts overheating again and the light comes back on. I am getting very frustrated and sick and tired of all this bull****. PLEASE HELP!!!!
The problem first started when I was getting no heat in my 2001 V6. We had the thermostat replaced, the heat worked for a bit, but then engine started to overheat. So we took it into Ford, they bled an air lock out, and car stopped overheating. Then we found some coolant leaks, so we replaced the thermostat again, replaced the top rad hose, and was still leaking. We then found out it was a crack in the water pump so we replaced that last week. Now there's no leaks, BUT it's overheating again!!! So we brought it back, they bled another air lock out, and did a head gasket check. No leaks coming from anywhere, seemed like it was just another air lock. But nope, today it starts overheating again and the light comes back on. I am getting very frustrated and sick and tired of all this bull****. PLEASE HELP!!!!
Thread Starter
Joined: Apr 2010
Posts: 15
From: Canada
update
update..... took my car for a ride and tried a few things. the car doesn't overheat UNTIL i turn the heat on, and thats when it starts climbing gradually up to hot. when i turn the heat off it slowly goes back down normal, and it also goes back to normal if i just let it idle after driving it. i then took it for another spin and turned the a/c on; didn't overheat! could this have something to do with my heater core? any suggestions? please help!! 
1st Gear Member
Joined: Jan 2005
Posts: 127
From: Corryton, TN 37721
I can understand about it runs normally with the A/C on as when you turn on the A/C, the electric cooling fan for the radiator also comes on. I am assuming it has a electric cooling fan. Does not make a lot of sense when you turn on the heater, it over heats. An old trick when you have a car over heating is to turn the heater on to provide extra cooling like having another smaller radiator. My thoughts air in system or thermostat switch for the fan is not kicking in the fan when it reaches the proper temperature so it over heats. If the heater core is not leaking, it is probably OK. Good luck, and I am confused over this one!
2nd Gear Member
Joined: Sep 2007
Posts: 361
From: Oklahoma
So your fan is for sure working? Did you turn the heater on while the car was still or were you driving with the heater on? When you get a chance, let your car get up to normal temp and see if the fan comes on (don't turn on the a/c or the heat, even though heat doesn't make the fan turn on). I'm really thinking its your fan.
Thread Starter
Joined: Apr 2010
Posts: 15
From: Canada
We thought it might be the fans too, but we checked, and the fans work perfectly! It's not an air lock either, we just got the air purged out a couple of days ago. I drove the car for long drives without the heat on, and it doesn't overheat at all, temp stays at normal. But as soon as I turn the heat on, a couple minutes after, it starts to overheat. When I turn the heat off, it gradually goes back to normal. So it's not the fans, they work fine. Any other suggestions? Heater core, blockage, bad radiator? Thanks guys!
2nd Gear Member
Joined: Sep 2007
Posts: 361
From: Oklahoma
The thing is, coolant always flows through your heater core whether you have the heat on or not(If I'm msitaken feel free to correct me). Your radiator really doesn't have anything to do with your heater.
1st Gear Member
Joined: Jan 2005
Posts: 127
From: Corryton, TN 37721
I have never heard of a car overheating when you turn the heater on either. Does it blow hot air when it is turned to heat? If so the heater core seems to be working, and is not blocked. My understanding of the heater is when you adjust the temperature control, you are adjusting the amount of heat that the blower picks up from the heater core. Actually controlling the opening of a plenum door that lets more air flow thru the heater core, more or less, depending on where the temperature control is set. Good luck.
Thread Starter
Joined: Apr 2010
Posts: 15
From: Canada
:icon_gunhead:
i've never heard of a car overheating with only the heat on either, and i was actually driving the car again today to get it looked at (for the 40th f-in time) and it started to overheat a bit when the heat wasn't on, which is a first in the last week. could it have anything to do with the water pump being installed wrong? there are no leaks coming from anywhere, we're completely stumped.....
