Warped Heads?

[canubaru]

Originally Posted by duckamuk

Last, this might be blasphemy, but I've read some posts of people using additives to seal gasket leaks - any opinions on these type of products?

yes for some subarus and additives. the official ''coolant conditioner'' from the dealer for 00 - 04+ SOHC engines that tend to have the external gasket coolant leak.

no for every other product and every other engine, Especially the 96 - 98 ej25 DOHC engine. nothing helps those except replacing with subaru gaskets.

i hope you got your fixed.

[jbwood5]

My opinion is that there is currently nothing wrong with your car. After a 500 mile trip with not a blip on the temp gauge and no loss of coolant pretty much tells the story. You would know by now if combustion gases were getting in the coolant from a bad headgasket. The original diagnoses was incorrect and I would not go looking for trouble.

[subiesailor]

Originally Posted by jbwood5

My opinion is that there is currently nothing wrong with your car. After a 500 mile trip with not a blip on the temp gauge and no loss of coolant pretty much tells the story. You would know by now if combustion gases were getting in the coolant from a bad headgasket. The original diagnoses was incorrect and I would not go looking for trouble.

Correct no car with a blown HG will do 500 mile trip without some type of coolant loss and temp spikes which are quite obvious. Don't mess with it

[duckamuk]

The latest is that now when I drive it with the heat on I get warm air coming out from the driver side vents, and cold air coming out on the passenger side vents. The dash gauge doesn't show any change and I didn't notice any antifreeze smell. It's too dark out to see if I've lost any coolant, but this was a short trip into town. Does this indicate anything? Unfortunately my mechanic can't take the car until Wednesday to check it out. I'll check that in the morning.

[frankspinz]

Perhaps this thread can shed some light:
Passenger Heat Issue??

Sediments or air can interfere with collant flow:

Originally Posted by plain OM

I've never taken down the heater duct system so can't answer with a high degree of knowledge, but based on my understanding (service manual etc) of how the system is put together, I don't think debris would be a likely factor. And given the similarity to the previous poster, where there was a cabin filter in place, it would seem there might be another reason for the difference.

A small temperature difference is considered "normal".

This is from February 2008 Subaru "TechTips":

" . . . We have received calls with a Customer concern of cold air coming out of the passenger side vents as compared to the driver side temperature which is quite warm. Keep in mind that up to a 15 degree variance is considered normal. In some cases, the condition arises after cooling system servicing but it can also happen with the vehicle’s original coolant. When draining and refilling the system, sediments become agitated and get re-circulated. Eventually, they collect in the heater core and restrict the coolant flow causing uneven temperatures across the core which result in inconsistent vent temperatures. Air pockets generated in the cooling system during the coolant replacement can create similar conditions. Vacuum-assisted cooling system re-filling tools . . . are a handy tool to help eliminate air pockets and the problems they can cause."

[duckamuk]

Originally Posted by frankspink

Perhaps this thread can shed some light:
Passenger Heat Issue??

Sediments or air can interfere with collant flow:

Thanks, I saw that post this morning. Don't know if it's a good or bad thing - if the gasket is leaking air into the system causing this, or it's just a function of the recent coolant change. Hopefully I'll have better info tomorrow.

[duckamuk]

Brought the car to my other mechanic this morning, who determined there's nothing wrong with the head gasket!
He pressure tested the cooling system and found no head gasket leaks. Also performed a hydrocarbon test and found no signs of gases in the cooling system! As for the cold air coming out on the passenger side vents they said it was the right side blend door actuator needs to be replaced.
He also asked me which Subaru dealer I used because he's recently had two other Subaru's in for other problems that a local dealer mis-diagnosed. Wasn't my dealer, but it doesn't bode well for Subaru service in Northeast Pennsylvania.
Thanks to all for your input!

[frankspinz]

Originally Posted by duckamuk

...Thanks to all for your input!

These Forums are great aren't they !? Glad this turned out to your advantage...