heartless Posted November 23, 2022 Share Posted November 23, 2022 21 hours ago, Daskuppler said: I had a smell of coolant in the garage a couple days ago but there were no visible leaks and no coolant on the floor. you thoroughly checked the top of the block - on the drivers side? there is a tube that runs from front to back along the drivers side - inboard of the head, but hidden by the intake - that is often a culprit in situations like this... not usually all that obvious unless you have a clue what you are looking for. 1 Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted November 23, 2022 Share Posted November 23, 2022 Do you have a pressure tester? 1 Quote Link to comment Share on other sites More sharing options...
azdave Posted November 23, 2022 Share Posted November 23, 2022 Heater output instantly going on and off can pretty much only be caused by low coolant levels. Either you still have a big air pocket in the system or you are loosing coolant. When you completed the last water pump repair, did you have good heat for multiple days in a row but now the heat is once again intermittent? If so, you have to be loosing coolant somewhere and if it's not on the ground and not soaked into the carpet inside the car then are you burning it in a cylinder? 7 hours ago, jonathan909 said: Do you have a pressure tester? I was going to suggest the same thing but be careful. If there is a head gasket leak, you could accidentally fill a cylinder with coolant and then the next time you try to start the engine it may hydro-lock and bend a rod. If you perform a pressure test and have any concerns afterwards that coolant might be leaked inside a cylinder, either manually turn the engine over several times slowly using a wrench on crank or pull the spark plugs before you ever touch the starter. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 14 hours ago, heartless said: you thoroughly checked the top of the block - on the drivers side? there is a tube that runs from front to back along the drivers side - inboard of the head, but hidden by the intake - that is often a culprit in situations like this... not usually all that obvious unless you have a clue what you are looking for. Are you referring to the two pipes/hoses that end up going through the firewall to what I assume is the heater core? There some some buildup on the front of the block but I think it's from the oil filler tube and is pretty oily. Would it be best to check when it's hot and see if there is any steam or localized odor under pressure? The smell of coolant is strongest at the top of the block and towards the front. The heat has not gone out since and there have been several heat cycles. I did notice some debris on the radiator fill port so I wiped that off in case it was preventing the radiator cap (new from Subaru) from completely sealing. When the radiator was out for the water pump and timing repair it looked sound (it's only got 15k or so on it), I did not see any green residue buildup or obvious signs of leaks. I replaced the lower radiator hose, the top was in good shape. Coolant levels were spot on the full line in the overflow and the radiator did not take more than a couple of ounces before it was overflowing. 11 hours ago, jonathan909 said: Do you have a pressure tester? I do not, but I can get one if that seems like the best rout to go. Quote Link to comment Share on other sites More sharing options...
heartless Posted November 23, 2022 Share Posted November 23, 2022 17 minutes ago, Daskuppler said: Are you referring to the two pipes/hoses that end up going through the firewall to what I assume is the heater core? There some some buildup on the front of the block but I think it's from the oil filler tube and is pretty oily. Would it be best to check when it's hot and see if there is any steam or localized odor under pressure? The smell of coolant is strongest at the top of the block and towards the front. The heat has not gone out since and there have been several heat cycles. I did notice some debris on the radiator fill port so I wiped that off in case it was preventing the radiator cap (new from Subaru) from completely sealing. When the radiator was out for the water pump and timing repair it looked sound (it's only got 15k or so on it), I did not see any green residue buildup or obvious signs of leaks. I replaced the lower radiator hose, the top was in good shape. Coolant levels were spot on the full line in the overflow and the radiator did not take more than a couple of ounces before it was overflowing. I do not, but I can get one if that seems like the best rout to go. pressure tester would be a good idea and could help you pinpoint any small leaks. and yeah, i am referring to those lines, but one in particular... if you look here: http://opposedforces.com/parts/impreza/us_g11/type_2/cooling_system/water_pipe_1/ the one i am specifically referring to is shown at the bottom of that image, and has a small offshoot that goes to the throttle body (the small hose at the top right is the one that connects to the throttle body).. that junction is often a failure point - have run into this twice over the years, once with a 2.2 Legacy and once with a 2.5 forester... If you follow the hoses from the firewall back to the engine, one will connect to the upper, large aluminum crossover, the other, slightly lower, will connect to the tube in question here. you could have a small leak that is not bad, yet, but will get worse over time - IF this is the source of your problem. a small leak will cook off lost antifreeze fairly quickly, but it will pool more as it gets worse... look for any signs of dampness on the top of the block in the region of that small offshoot line. So yes, checking while running is not a bad idea. that particular pipe is listed with the water pump in the diagrams (for part numbers) - seen here: http://opposedforces.com/parts/impreza/us_g11/type_2/cooling_system/water_pump/ It is also possible that the wrong radiator cap was the primary source of your problem and the system is simply working out air bubbles now (temporary loss of heat). Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted November 23, 2022 Share Posted November 23, 2022 Noting @azdave's caveat, it may not be the best way to go, but it's another way to go. The (obvious) problem is that there's only so much poking around you can do with a hot/running engine without risk of getting burned, your leg sucked into a spinning belt, etc. Looking while hot gives you the advantage of spotting steam, but a cold pressure test lets you get in closer. First see if it holds pressure. If not, the next questions are why and where. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 28 minutes ago, heartless said: pressure tester would be a good idea and could help you pinpoint any small leaks. and yeah, i am referring to those lines, but one in particular... if you look here: http://opposedforces.com/parts/impreza/us_g11/type_2/cooling_system/water_pipe_1/ the one i am specifically referring to is shown at the bottom of that image, and has a small offshoot that goes to the throttle body (the small hose at the top right is the one that connects to the throttle body).. that junction is often a failure point - have run into this twice over the years, once with a 2.2 Legacy and once with a 2.5 forester... If you follow the hoses from the firewall back to the engine, one will connect to the upper, large aluminum crossover, the other, slightly lower, will connect to the tube in question here. you could have a small leak that is not bad, yet, but will get worse over time - IF this is the source of your problem. a small leak will cook off lost antifreeze fairly quickly, but it will pool more as it gets worse... look for any signs of dampness on the top of the block in the region of that small offshoot line. So yes, checking while running is not a bad idea. that particular pipe is listed with the water pump in the diagrams (for part numbers) - seen here: http://opposedforces.com/parts/impreza/us_g11/type_2/cooling_system/water_pump/ It is also possible that the wrong radiator cap was the primary source of your problem and the system is simply working out air bubbles now (temporary loss of heat). I looked in that area, there was a lot of debris but almost all of it blew out with a compressor. There was a little bit of stuff on the hard pipe, but it wiped off and was mostly just dust. The block has a little bit of stuff stuck to it that wasn't removed with compressed air, but no real signs of a leak here. 27 minutes ago, jonathan909 said: Noting @azdave's caveat, it may not be the best way to go, but it's another way to go. The (obvious) problem is that there's only so much poking around you can do with a hot/running engine without risk of getting burned, your leg sucked into a spinning belt, etc. Looking while hot gives you the advantage of spotting steam, but a cold pressure test lets you get in closer. First see if it holds pressure. If not, the next questions are why and where. The auto parts store rents them locally so I'll go grab one and see what happens. I don't think it's likely to be head gaskets as I don't have any of the other symptoms I've had in the past. 1 Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted November 23, 2022 Share Posted November 23, 2022 (edited) 40 minutes ago, Daskuppler said: I looked in that area, there was a lot of debris but almost all of it blew out with a compressor. There was a little bit of stuff on the hard pipe, but it wiped off and was mostly just dust. The block has a little bit of stuff stuck to it that wasn't removed with compressed air, but no real signs of a leak here. ... The auto parts store rents them locally so I'll go grab one and see what happens. I don't think it's likely to be head gaskets as I don't have any of the other symptoms I've had in the past. I'm a total tool queen, so if I can get even a cheapie to add to my permanent reserve (in this case it was a pressure tester from Princess Auto, which is sort of like our Harbor Freight), I'll do it regardless of how seldom I think I'll use it. It's about having as broad a range of tools in the arsenal as possible. Aside from the differences I mentioned above, consider that looking for the leak with the engine stopped and/or cold also means the fans won't be blowing drips, drops, and steam away from the actual source of the problem, and that you may be able to hear a hiss you wouldn't otherwise. An array of diagnostic tools means you're not relying on just one to contain all the necessary magic, as that's rarely the case. A different tool allows a different perspective on the problem. Edited November 23, 2022 by jonathan909 1 Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 10 minutes ago, jonathan909 said: I'm a total tool queen, so if I can get even a cheapie to add to my permanent reserve (in this case it was a pressure tester from Princess Auto, which is sort of like our Harbor Freight), I'll do it regardless of how seldom I think I'll use it. It's about having as broad a range of tools in the arsenal as possible. Aside from the differences I mentioned above, consider that looking for the leak with the engine stopped and/or cold also means the fans won't be blowing drips, drops, and steam away from the actual source of the problem, and that you may be able to hear a hiss you wouldn't otherwise. An array of diagnostic tools means you're not relying on just one to contain all the necessary magic, as that's rarely the case. A different tool allows a different perspective on the problem. I have quite a lot of tools as well and I usually purchase over rent, but I just rented this time (it ended up being brand new so there wasn't any abuse on this one). Pressure held at 23psi for 25 minute so I would assume there's no leaks unless the cap is bad but it's brand new from Subaru. A buddy said there is usually a vacuum driven actuator allowing hot coolant to flow to the heater core and that they can go bad. Is there something like that present on Subarus? Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted November 23, 2022 Share Posted November 23, 2022 (edited) I can't answer that one - I don't really know anything about the actuator and controls as I hate working in/under dashes so much that I've just been living with my '99 OBW's reluctance to change the airflow on command (e.g. from defrost to floor). In that case my suspicion is that the control PCB needs reflowing or replacement or something - I'm not having the kind of problem you are. Also, I don't know how representative a result you're going to get over <30 minutes. Myself, I'd pressure it up and leave it overnight. Consider that this leak may be (in part) a product of normal thermal expansion, and that it may be a smaller aperture when cold. Edited November 23, 2022 by jonathan909 Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 (edited) 1 hour ago, jonathan909 said: I can't answer that one - I don't really know anything about the actuator and controls as I hate working in/under dashes so much that I've just been living with my '99 OBW's reluctance to change the airflow on command (e.g. from defrost to floor). In that case my suspicion is that the control PCB needs reflowing or replacement or something - I'm not having the kind of problem you are. Also, I don't know how representative a result you're going to get over <30 minutes. Myself, I'd pressure it up and leave it overnight. Consider that this leak may be (in part) a product of normal thermal expansion, and that it may be a smaller aperture when cold. The kit only said 2 minutes and I saw 10 minutes pretty commonly online so I just kinda picked an arbitrary number. I can run it again longer, the radiator attachment didn't want to seal terribly well (I could hear it leaking if things weren't perfectly set) so I didn't want to leave it to long, I figured the results would be moot anyway. I was hoping but over pressurizing I could push it to leak a little more even if it was a small leak. It might be worth buying a kit. For what it's worth, the engine was cold during the test and had been sitting for 12 plus hours, the garage was 35 degrees. Edited November 23, 2022 by Daskuppler Quote Link to comment Share on other sites More sharing options...
Numbchux Posted November 23, 2022 Share Posted November 23, 2022 1 hour ago, Daskuppler said: A buddy said there is usually a vacuum driven actuator allowing hot coolant to flow to the heater core and that they can go bad. Is there something like that present on Subarus? No, Subarus have constant flow through the heater core, and divert the air around it to adjust the temperature. 1 Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 12 minutes ago, Numbchux said: No, Subarus have constant flow through the heater core, and divert the air around it to adjust the temperature. Awesome thank you. He's not familiar with Subaru so I figured I'd check here. Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted November 23, 2022 Share Posted November 23, 2022 Hmm. I didn't see any mention of "running bubbles" in the coolant overflow, but is it worth doing a compression test? Hardly definitive, but maybe something turns up. I don't think I've ever head anyone mention "airhead" adapters on here - the shop air adapters that take the place of the spark plug and let you pressure up the cylinder without running or cranking. Quote Link to comment Share on other sites More sharing options...
Ferret54 Posted November 23, 2022 Share Posted November 23, 2022 Does this have manual heater controls? or Auto? ..... If it's the Auto controls, maybe the control or the cabin temp sensor is malfunctioning. Or maybe when failing, you could feel or check the temp of the supply and return hoses under the hood by the firewall to determine if hot water is flowing.... I know a shot in the dark. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 12 minutes ago, Ferret54 said: Does this have manual heater controls? or Auto? ..... If it's the Auto controls, maybe the control or the cabin temp sensor is malfunctioning. Or maybe when failing, you could feel or check the temp of the supply and return hoses under the hood by the firewall to determine if hot water is flowing.... I know a shot in the dark. They are manual controls and cable driven. I can hear the blender door moving so I don't think that's the problem but who knows. I'll see if I can check temperatures on the hoses, that might be hard but could be helpful information. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 23, 2022 Author Share Posted November 23, 2022 27 minutes ago, jonathan909 said: Hmm. I didn't see any mention of "running bubbles" in the coolant overflow, but is it worth doing a compression test? Hardly definitive, but maybe something turns up. I don't think I've ever head anyone mention "airhead" adapters on here - the shop air adapters that take the place of the spark plug and let you pressure up the cylinder without running or cranking. I have not done a.compression test. The head gaskets have about 60k on them and I don't really have any other symptoms. Exhaust smells normal, car starts and runs fine, and the heat doesn't come and go on a drive. If it's gone when in it starts, it's always come back in a few minutes and never disappears after that. Reving the engine to move coolant and bubbles doesn't help. Temperature gauge is rock solid as well. I guess I could. Pull spark plugs and check for coolant. We'll see how it progresses. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 29, 2022 Author Share Posted November 29, 2022 The other day I was driving around and the heat wasn't working terribly well. After about 5 minutes of luke warm air, there was an audible change and then the air was hot. I started messing around with it and I believe the blender door is not actuating fully to the hot side until things warm up a little. Is this a greasable part? Would replacing the blender door cable fix the issue (it's very stiff when cold)? Quote Link to comment Share on other sites More sharing options...
nvu Posted November 29, 2022 Share Posted November 29, 2022 (edited) The blender door cable is a solid core wire, they last forever. You'd have to take apart the hvac unit to replace the cable anyways. Maybe try cycling the door a lot once it's hot, hopefully it frees up things. Also no way to grease things as the mechanism is inside the hvac unit Edited November 29, 2022 by nvu Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 29, 2022 Author Share Posted November 29, 2022 1 hour ago, nvu said: The blender door cable is a solid core wire, they last forever. You'd have to take apart the hvac unit to replace the cable anyways. Maybe try cycling the door a lot once it's hot, hopefully it frees up things. Also no way to grease things as the mechanism is inside the hvac unit Okay, thanks! It's been stiff for years. Oh well. Quote Link to comment Share on other sites More sharing options...
nvu Posted November 29, 2022 Share Posted November 29, 2022 My bad, the cable is detachable on your model from the hvac unit. You should be able to get to it by taking off the lower drivers side dash only. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted November 30, 2022 Author Share Posted November 30, 2022 (edited) 1 hour ago, nvu said: My bad, the cable is detachable on your model from the hvac unit. You should be able to get to it by taking off the lower drivers side dash only. Great news! Looks like it's only about $11. That should help a little haha. Edited November 30, 2022 by Daskuppler Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted December 11, 2022 Author Share Posted December 11, 2022 (edited) I went to replace the cable (the old one was very stiff when I removed it), and the actuator arm on the blend door snapped off inside the housing. I tried JB Kwik Weld, but that didn't work. The arm must have moved while I was taking it off as the air coming out of the vents is warm at best. Any chance this little arm can be replaced or do I need the whole blend box assembly doohickey? Is there a write-up anywhere on how to do it? I looked around on the internet and didn't see anything specific to this generation Subaru...Lots of american cars but nothing helpful. A brief search through the Subaru Parts website shows that pretty much everything related to the HVAC is unavailable but I don't really know what I'm looking for so it's hard to check availability. Edited December 12, 2022 by Daskuppler Quote Link to comment Share on other sites More sharing options...
lmdew Posted December 12, 2022 Share Posted December 12, 2022 You will need to pull the complete dash out to get the heater box apart. I'd hit the self-serve yards in the area and do it there first. It's a job for sure. Not to hard but it takes time. You may find a car with the dash pulled out already to give you a good view. Quote Link to comment Share on other sites More sharing options...
Daskuppler Posted December 12, 2022 Author Share Posted December 12, 2022 1 hour ago, lmdew said: You will need to pull the complete dash out to get the heater box apart. I'd hit the self-serve yards in the area and do it there first. It's a job for sure. Not to hard but it takes time. You may find a car with the dash pulled out already to give you a good view. So that piece is only available with a heater box assembly? Quote Link to comment Share on other sites More sharing options...
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