Subaru Outback knock sensor

Question

Love your videos, thanks for the information.

I have a Subaru Outback Legacy 2001 2.5l 4cyl Standard Transmission and I'm having a problem getting it to pass emissions. I had the engine rebuilt a wile back, full overhall, sleeved pistons etc. it ran great for a while but now the knock sensor ecu code P0325 wont go off, Ive replaced the knock sensor twice with OEM parts and even tried changing the engine timing to no luck. Is there anything else that I may be missing or is my engine actually knocking or my ecu messed up? All the mechanics have no idea whats wrong. I may have to take it to the dealership. Just afraid they might just try to sell me a new car.

The car has also been overheating and it seems like the fan isn't turning on when it needs to. It looks like the ABS is disabled but I think thats due to the check engine light being indicated.

Thanks & best regards.

atkf213 · Answer

The car has been babied all its life, owned by an elderly person as their daily driver, it was garaged & maintained meticulously the entire time. Only reason it needed an engine rebuild was because what Scotty outlined in one of his videos happened. I guess she did a cheap oil change before a road trip & either they didn't put oil in or screw the filter on & boom.

Chuck Tobias · Answer

Is the wiring from the knock sensor to the ECU in good shape? (Maybe check with continuity tester?) Also try cleaning connector contacts on the ECU and make sure grounds are OK.

A Subaru stealership is unlikely to have anyone that is familiar with your car - most of the mechanics were probably in kindergarten, some maybe not even born yet, when it was made. You'll be charged a fortune and you're unlikely to see a good result. Aside from replacing the sensor, what steps have the mechanics you've gone to taken to diagnose the problem? An independent mechanic who is specifically familiar with Subarus of that vintage would be the best bet if you can find one.

The fan not turning on could be due to a bad temperature sensor, bad fuse, bad relay, bad fan motor, bad wiring. The car may have been babied aside from the bad oil change but it's still 20 years old.

The ABS problem is most likely a bad wheel sensor.