what is this phantom knock?

[nuclearpenguin]

I have terrible phantom knock, let me describe everything I know about it:

-It's occurence is 100% random. Cold weather, hot weather, when the motor is warm, when the motor is cold, but it's intermittent. It occurs probably 80-90% of the time that I'm accelerating.

-Sometimes I'll accelerate, it'll knock like crazy, I'll drive for another minute or a few and accelerate hard again and it doesn't knock at all. (again, completely random).

-I have a "fair" amount of lifter tick, but it's not terrible.

-If I'm cruising steadily or decelerating, it won't happen until I accelerate a little bit. But it happens at part throttle or full throttle, all ranges of RPMs.

-I already replaced the knock sensor already with mitsu OEM and didn't over tighten it (about handtight plus 1/8-1/4 turn further with a wrench).

-It's usually 43 counts, but sometimes varies a little bit.

Any ideas of what it could be?

 

[andymoraitis]

You may bought a bad knock sensor. It happens. I'd try another known working unit just to be sure. For reference, correct torque is 17 lb/ft. You could also have an issue with the ECU. I'd pull it out and check for leaking caps or a rotten egg smell.

 

[BISHILVR]

Sounds exactly like mine.

 

[nuclearpenguin]

You may bought a bad knock sensor. It happens. I'd try another known working unit just to be sure. For reference, correct torque is 17 lb/ft. You could also have an issue with the ECU. I'd pull it out and check for leaking caps or a rotten egg smell.

The only reason I think it's not the KS is because it's the exact same symptoms as the last KS had, only slightly less occurring.

I am gonna be toying with the ecu tomorrow when installing my new afc, I think I'll pull it out to check if it's eprom and I'll be sure to look over the caps.

 

[95blackGsTurbo]

Phantom knock basically is a audible noise that the knock sensor is picking up that isn't knock.

 

[nuclearpenguin]

Ugh, opened up the ECU. No EPROM AND that icky rotten seafood smell we all dread.

I'm gonna harness down my exhaust (it rattles pretty bad), hoping that's at least 1 of the things the sensor is reading as knock.

Anything else I should check for?

 

[Decker0004]

If you smell fish it’s going to be bad 9 times out of 10. It’s going to be hard to gauge anything until you get the ECU fixed. Steve, one of members, is excellent at fixing ECUs. You should PM him and see what he thinks. I had all sorts of problems with my car until I sent my ECU to Steve.

Travis