Just bought a 1997 Legacy GT with the 2.5, it has a hesitation. If you're driving along on a flat road and low load on the motor motor cuts out like a kill switch was hit. If I push down on the accelerator a little, nothing happens. If I push down further, with a jerk the motor comes back and everything runs right. I have a set of plug wires and upstream/downstream due to arrive this week.

 

I see someone connected the two knock sensor wires together, the sensor is also still in place. Could this be the problem? Or maybe the problem causes the engine to jerk and throw a knock code and this is how he alleviated it? TIA!

subaru changed the wire connector to the knock sensor in the late 90s, 98 i think. they went from a one wire set up to a 2 wire set up. the second wire is just a ground, the earlier version relied on the block for the ground. adding the ground wire helped / tried to eliminate corrosion between the sensor and the block causing issues. this is very common in automotive stuff.

 

the knock sensor didn't change, i don't think.

 

sounds like some one installed the wrong sensor or screwed it up.

 

are you saying the wires are tied together and the sensor has been removed from the circuit. that would cause knocking, i think. if the car is not knocking i doubt the wires are causing your issues.

 

but the sensor could be tired and not working properly.

Edited January 4, 201115 yr by johnceggleston