I’m not a mechanic or even a car nut, but I’m good with tools and can think critically.
-2012 2.5i Limited Outback
-It gets very hot when driving slowly, but not at highway speeds. I can drive for 40 minutes no problem, as soon as I get on secondary roads the temperature starts to rise. Coolant is drained from the overflow tank when the temperature rises to about 230 degrees. While on the highway the temp stays around 190-195, maybe 200. (I’m driving with my OBD plugged in until this is fixed). As soon as I slow down going into town the temperature rises until I go fast again (45+) or I pull over and let it cool down.
I replaced the thermostat, radiator cap, and coolant temp sensor (all non-OEM), flushed and refilled the coolant (Blue Stuff They Say for 2008+ Subaru Outback from Advanced Auto Parts)
– Coolant expansion tank pipe is not blocked or kinked
-I lose heat in the cabin when the temperature starts to rise above 210 or so
-The coolant still looks clear, no sludge anywhere
– System pressure test shows no leaks, pressure needle holds steady for 10 minutes at 25 psi
-The fans seem to work fine on low and high, but when the car overheats, the fans blow cold air as if no coolant is circulating.
I thought if the water pump seized I would be in big trouble but on the highway it seems fine.
I am at a loss as to what to do or check next. I thought maybe an air bubble in the system was causing intermittent overheating, but screwed it up and still having issues. Plus, shouldn’t air bubbles get into the expansion/fill tank and be eliminated?
I pressure tested the old radiator cap and it wouldn’t release pressure no matter how high I pumped it up, so it was replaced. A new one releases like 20psi instead of 16 which is the rated release pressure.
Please help.
