P0328 Subaru -

Question

I have a 2002 suburua outback with the code p0328 knock sensor 1 high input bank.another code p0447 evaporative emission system vent control circuit open,another P0420catalyst system efficiency below threshold bank 1.i am having an issue of the car losing power and then will stutter a bit and all of a sudden it will gain full power again the loss of power seems like it suddenly loses power even while throttle at full I've even backed off and tried shifting the automatic tranni to see if it makes a difference but it doesn't.I am curious as to what code comming up may be causing this issue.thanks kindly.

Answer 1

Hi there,

Of the codes you are showing, the catalytic converter code would be the one most likely to cause this type of issue. if there is loose catalyst inside bouncing around it may be plugging up the exhaust flow and causing the problem.

The P0328 is also important because it helps the computer regulate the timing, but the symptoms you are describing would likely be related to the converter.

The P0440 code is an evap emissions code and isn't a factor.