2.3 4cyl running Hot... Please Help!

[Bigjon]

Hi, I'm Jonathan! I have a 2002 ford ranger, 2.3 4 cylinder engine, with 140,000 miles, and it runs hot with the a/c on when driving up a steep grade. It's been doing this for the past 2 years. It never runs hot in the winter. Only the summer time, and you can drive around all day with the a/c on, and it will never run hot until you start up a mountain, and I live in the mountains, so it's kind of hard to avoid. When it starts running hot, you can turn the heater on, and the temp gauge falls back down to normal in a split second. It don't just gradually come down. It literally falls back down in the blink of an eye as soon as you flip on the heater. I've been told that it's just a bad temp gauge, but I know that's not it, cause when it does this the overflow tank fills completely full of antifreeze, and looks like it's going to pop, so I know it's getting hot. I have installed a new fan clutch and flushed out the radiator, and neither has helped. I've talked to some good mechanics around here, and all of them says that it's not the thermostat or water pump. They all say that I just need a new radiator, but I have a friend that is having the same exact problems with his truck that I'm having with mine, and a new radiator has not helped his one bit, so I'm not sure that's the problem either. I'm not loosing any water or antifreeze. Does anyone have any idea of what it could be? Please Help... Thank You!

[ford4thot]

Head gasket going out? Maybe

[djfllmn]

im gonna say its just the combination of hot weather, AC running, and the motor under a load...try making sure the coolant is mixed in the proper ratio and the radiator and ac condenser are clean

[96_4x4_XLT]

Originally Posted by Bigjon

Hi, I'm Jonathan! I have a 2002 ford ranger, 2.3 4 cylinder engine, with 140,000 miles, and it runs hot with the a/c on when driving up a steep grade. It's been doing this for the past 2 years. It never runs hot in the winter. Only the summer time, and you can drive around all day with the a/c on, and it will never run hot until you start up a mountain, and I live in the mountains, so it's kind of hard to avoid. When it starts running hot, you can turn the heater on, and the temp gauge falls back down to normal in a split second. It don't just gradually come down. It literally falls back down in the blink of an eye as soon as you flip on the heater. I've been told that it's just a bad temp gauge, but I know that's not it, cause when it does this the overflow tank fills completely full of antifreeze, and looks like it's going to pop, so I know it's getting hot. I have installed a new fan clutch and flushed out the radiator, and neither has helped. I've talked to some good mechanics around here, and all of them says that it's not the thermostat or water pump. They all say that I just need a new radiator, but I have a friend that is having the same exact problems with his truck that I'm having with mine, and a new radiator has not helped his one bit, so I'm not sure that's the problem either. I'm not loosing any water or antifreeze. Does anyone have any idea of what it could be? Please Help... Thank You!

engine under load AC on and in the summertime
hmmm
X2 with DJ make sure your coolant is full

sent from my iPhone 5....PSH!!! I don't have money for a iPhone 5

[black 06 ranger]

Thermostat. Switch it out and see. I had a car that did the same thing and I drove it like that for 2 yrs.

[Bigjon]

Thanks everybody! I will certainly take all this advice into consideration and see what I can come up with.