I have a 2011 Subaru Legacy 2.5i Limited with only 62,000 original miles. Here's the story - I'm looking for any input that can help as my mechanic and I are stumped at this point:
The car started randomly overheating a couple months ago, blowing coolant out of the coolant reserovoir tank. Parts replaced so far, all with OE parts -
1. Radiator
2. Upper and Lower Hoses.
3. Thermostat (twice).
4. Radiator Cap.
5. Coolant Temp Sensor.
6. System Flushed twice, coolant is Subaru Blue.
7. Fans checked and working properly.
8. System pressure tested (twice) - passed.
9. Ran test for exhaust gases in the coolant and no issue there.
10. Car has been run connected to diagnostic computer and temp not going higher than 208.
11. No check engine lights, only blinks red temp symbol and overheats.
12. Both upper and lower hoses get warm but bottom hose temp a little lower than top.
13. No issues with getting heat in cabin.
14. Water pump is circulating coolant in the radiator, its only a little over 3 years old and the impeller is steel, not plastic.
I just got off the phone with my mechanic and in lieu of all this, you can only get 7-8 miles before it overheats and the fans are running properly.
He scanned entire route of cooling system with a temp gun and temps were consistent with the exception of one abnormality - there is a coolant crossover hose that he said is in the intake and is about 12 inches long. On one end of the tube the temp is 165, on the other it is 208.
He's now thinking we're down to only 2 possibilities -
1. That crossover tub is clogged somehow, prohibiting proper coolant circulation through the system.
2. Even though the water pump is circulating coolant, its not working properly and not circulating it at the rate needed.
He really does not think its the Head Gasket.
I'm about ready to trade the car in although I don't want to. Any ideas or other things to look at would be most appreciated. At my wit's end with this. Thank you in advance for any input or ideas.