Ectell

Guys at m45 say it's a head gasket, so I am tearing the car apart now. Going to go with their recommended six star mls head gaskets and get some new ARP head studs at the same time. Also taking the heads to get machined at their shop. Is their any other recommendations that you guys have while everything is apart? I still don't know these cars so we'll, so I would appreciate any advice you guys have.

Ive made an appointment on friday with a local shop called M45. They are a specialty subaru shop with good ratings, so I'm hoping they can help me out. The technician I talked to suspected the head bolts could be an issue, as he had the same thing happen to his legacy. Thanks for the recommendations, I will update the thread after the appointment.

Yeah max, you are probably right. It's the next step I should take in case it isn't the head gasket. Im stubborn about working on cars myself. I don't like taking my cars anywhere for other people to fix. But I don't know a lot about these cars yet. I'll look into some local places.

I'm starting to really suspect the head gasket is the ultimate cause of my problem. Whenever I drive it and lean a bit on the turbo, the coolant in the turbo tank gets displaced and doesn't fully refill on cool down. Probably the exhaust gasses displacing the fluid and filling the reservoir. I don't know why the block tests are always negative, and the cooling system easily passes any pressure tests, but head gasket is the only thing I think it could be at this point. Thanks for all the replies guys, it was helpful. I've gotta try to figure out my next move for this thing. Times being what they are, I've got to find a cheap way to get this thing on the road again. I've always looked at head gasket repair chemicals as snake oil, so I have never used them. Does anyone have any advice on if the stuff works at all, or if it is just snake oil? I'm also capable of doing my own repairs as far as wrenching on a car goes. Is it possible to do a head gasket job with the engine in the car? Does anyone have head gasket brand recommendations?

I did the block test once in the overflow with bubbles directly under the tester, and it was negative. Did it again later on the radiator directly and it was also negative.

I bought all new caps when I was having issues, hoping for the easy and cheap fix, but it didn't work. I have the oem ones in the correct positions. I also tested them, and they seem fine. ( One is around 15 psi and the other one is around 20)

Yeah, it never goes over the middle of the temp gauge. Thing just overflowed on me again. I got 2 drives out of it and everything was going well, but decided to drive it a bit more aggressively this time. When I stopped, the coolant was overflowing from the expansion tank again. I am thinking the issue only occurs if I engage the turbo for a decent amount of boost.

I burped the car several times. I burped it with the turbo tank open, but after that I had the overflow issue. So I burped it again by lifting the front end of the car until the radiator got to be the highest spot on the system, and burped it through the radiator. Still had issues, so I got a no spill funnel and burped it again using that on the turbo tank jacking up just the front passenger side of the car. All those times I had the heat on full blast with the fan on low. What I Meant by levels being completely full is the coolant levels in all the reservoirs. Completely full radiator, completely full turbo tank and the expansion tank at the full mark. When I inserted the caps on the turbo tank and radiator, I literally spilled coolant because it was so full. I was convinced that there was too much air in the system. But the expansion tank would overflow and the levels in the radiator and turbo tank dropped. The turbo tank could be half, to three quarters empty when I checked it after the car cooled completely from a drive. I started thinking something was letting air into the system, so I replaced both radiator caps and most of the hoses attached to the turbo tank, and the turbo tank itself.

Thanks for all the advice, I'm still trying to learn more about how these cars work. The car seems to be leveling out now weirdly enough. I've taken it on a few more drives and it doesn't seem to want to overflow anymore. I think it just didn't like being completely full.

The tank next to the turbo is called the filler tank in my manual. The clear tank is always called the expansion tank in it too. I service the expansion tank to the low mark when it is cold, and fill the filler tank completely. But the filler tank is always half empty after I drove around, and the expansion tank tries to overflow, or come close to it. I flushed the system because it had been a few years since it had been done and just wanted to be thorough.

Yeah, I have done multiple hydrocarbon tests and they were always negative. The car only has 10000 miles on it since it got a brand new block, so I'm hoping it's not a head gasket. It doesn't bubble at all at idle if I just let it warm up, and it never overheats. I think it only bubbles when the turbo engages. I know that the car is supposed to flow coolant through the turbo and it gets hot as anything. Maybe it's just mass dumping coolant after getting heated by the turbo. It does seem to level out in the expansion tank sometimes. I just don't like that the filler tank is always half empty when I check it.

It sounds like you have a scanner. You could see if you have any input from any of your fuel systems while trying to crank the engine. Sometimes the front O2 sensor going out can cause a lot of weirdness without setting off any codes. You could also try cleaning out any connections for the fuel pump.

Hey guys, I was wondering if anyone could give some advice on an ongoing issue I've been having? I have coolant that was overflowing and bubbling out of my expansion tank following a coolant flush and refill that I did myself. Car is a 2006 GT automatic. The coolant bubbles can be seen after driving for 5-10 miles on a hot day. The level of the expansion tank goes from the low mark when cold, to overflowing after the drive. After shutting the car off, I can usually hear coolant pushing past the filler tank cap, into the expansion line. Ive also noticed that the filler tank always seems to be half empty after the system cools down again, which is odd because the coolant does seem to flow back into the filler tank as the coolant cools off. I did multiple block tests with the car running and bubbles right underneath the tester and its always been negative. I have done a pressure test up the nearly 20 psi and noticed zero pressure decrease after 3 hours. Left the tester on overnight and saw less than a psi of drop. Had a friend turn on the car and watched the exhaust and there was zero smoke after the pressure test. I have replaced both radiator caps, the filler tank, radiator hoses and almost all the filler tank hoses (only one left is the return to the expansion tank). I have also burped the system multiple times using a spill-less funnel both with the front jacked up and also just the passenger side. Both times ran the car until zero bubbles were visible. (including when I grabbed on the radiator hoses.) Im starting to think I'm being paranoid and creating my own problems, and this could be something as simple as the system being over serviced. Do these cars not stay full in their reservoirs by design? I filled the radiator to the point the cap pushed coolant out of it on its way in, and did the same for the filler tank. I usually service the expansion tank to the low mark when it is cold. Any advice or insight would be much appreciated.