2002 Subaru Outback 3.0 overheating

Please bear with me, I am typing up for my husband.

I own a 2002 Outback. It is overheating. We have replaced hoses, thermostat, water pump, the temp sensor, had the radiator tested. Nothing has changed our problem. My husband is at a loss and the mechanic who has is now has no clue as to what else it could be. The mechanic is referring to it as a ghost problem.

Have a pressure test done on the cooling system or a leak down test on the cylinders. More than likely a blown head gasket.

The mechanic said the head gasket was good.

The mechanic is wrong. A small head gasket leak puts tiny bubbles into the cooling system which eventually causes the overheating. It can be hard to detect by any test.

Agree; this car is subject to head gasket problems. The mechanic should do as suggested; if he still can’t find the leak, go to another and better mechanic.

You did not mention whether the cooling fan was operating properly. Have that checked as well.

Thank you for more insight. It is what I need at this point. I will pass this along.

Husband said he tested the fans and said yes it is operating properly.

How do I make sure I am going to a better mechanic. I have no clue if this was a good mechanic or not.

I was planning on calling Subaru on Monday.

Some more info may help.
Does it overheat at idle or slow speed only, only at highway speeds, with the A/C on or off (including DEF), etc, etc.

Does it get hot enough to boil over?

Mechanic Files link hopefully has a mechanic in your area.

We have noticed this spring when driving over the mountain passes the temperature would climb and sometimes would go back down. When we were driving around town it would do fine. But then as time would go it would spike and then go down. So this was a gradually thing till it was a definite problem.

When it fist started my husband changed the thermostat. It seemed to have helped until I got stranded one day because it overheated and died. I didn’t know it was overheating because the temp gauge stayed normal. Husband then changed the temp sensor. It now reads the correct temp, which is it gradually goes to the red when idling.
It does it with the AC off.

So this moment we are only seeing it overheat at idle. Have not taken it on a road test since it has been overheating by just idling.

Classic…head gasket.

I will hug you if thats it ! LOL I just want it fixed. I miss my car and so sad that we have had to waste so much money on this so far.

“this car is subject to head gasket problems”

Actually, while the 2.5 liter 4-cylinder engine is known for head gasket problems, the 3.0 liter six is not known for having that issue.

That being said, it does sound like a classic head gasket problem.

“I will hug you if thats it !”

When you hear the price for replacing both head gaskets, you may not want to hug anyone.

Got any rough estimates on how much to fix the head gasket?

I don’t know much about labor costs in Colorado, but I think that you should anticipate anywhere from $1,500-$1,800 for this repair. Remember that there are two head gaskets.

If the cylinder heads need to be machined, it could cost a bit more.

My hubby sent this to me. I just want to make sure all is covered.

Hubby-“OK. The issue is that the coolant is not flowing/circulating. Everything has been either tested or replaced.”

If you have a partially plugged radiator, the fix is much cheaper. You indicated that all this had been checked, but a failed water pump or plugged radiator will definitely cause overheating. The fact that in normal driving it does not overheat makes me suspect the radiator and/or water pump.

Since it was overheating while climbing mountain passes and not in town I might suspect a clogged radiator or partially clogged catalytic converters; assuming radiator fans are operating as they should.

If it only overheats at an idle now then I might suspect a cooling fan issue.

I may be wrong, and maybe someone else can opine.

Could your husband have put the thermostat in backwards???


How did your husband test the fans? If he just put power to them and they ran, he has to confirm that they come on by themselves when it is idling. Also did you check that the radiator was full when cold?