I have a 2001 legacy gt limited. I replaced a blown ej25 engine a operational engine I purchased from Lkq. I had no prior transmission problems but since engine swap the AT Temp light stays blinking continuously and the check engine light is on. The car does run but initially shifts hard in 1st 2 gears. The hard shifting does clear up after driving for a short distance. Have done numerous code checks and Subaru dealership had replaced transmission temp sensor. Still having problems and apparently the certified mechanics can't resolve this issue. So basically the AT Temp light blinks continuously, the check engine light stays on continuously. Car shifts hard initially than clears up on own after a few minutes . So called certified Subaru mechanic ran computer codes on it and said it was a temp sensor and code showed a -77 degree transmission fluid temp. Replaced that sensor $490.00 later and still little or no improvement. Is there a real mechanic out there that can help me?

My guess is a bad TPS on the new engine. Throttle position sensor is the only engine sensor the TCU cares about so I' d start there?

 

What is the engine code. That would be another place to start.

go to a parts store and get the obd codes read. report the pxxx code back here.

 

TPS is one issue that will throw a CEL and AT Temp light.

the MAF is another.

 

check the connectors for the maf , the TPS and the 3 connectors on the rear of the engine passenger side.

make sure they are clean, fully seated and that none of the pins are bent.

 

did you remove the TPS during the install? maybe to make room so you could get to the torque converter bolts. is yes, that is the issue.

 

i would ask for your money back from the dealer.

you paid $490 and they failed to fix your car.