sti146

Where do i start....
Car is an classic STI 6, owned by me since new, only mod is a turbo back exhaust.

A couple of weeks ago i had a check engine light come on. so i checked using ecu explorer and a tactrix cable. Was a Knock sensor error code. so i replaced the sensor with a new factory item, and deleted the code. reset ecu and away i went.

Now ive noticed im getting pinging even when the car is not under any load. i mean if i accelerate slowly in 1st and 2nd gears so im in vacumn car will begin to ping when i hit 4200rpm or so. if i hit boost it will also knock when at max boost level.
Ive data logged and the pinging is not registering on my logs, its like the knock sensor is not sending a signal back to the ecu to retard when it picks up the pinging. My AM gets to 16 and stays there, yet the car pings audiable when revs rise above about 4200 even with NO load which confuses me.
Ive replaced AFM, changed fuel...have always run 98 Octane, swapped another knock sensor...all the same!
Voltage from the knock sensor wiring with the sensor connected ( 550 ohms res) is 2V with Ign on and sensor grounded, book says 2.8V?? is this my problem?
Also when im data logging at idle, and tap the sensor bolt it wont register knock...is this normal..i.e. car must be in motion for it to work etc.
The car will even ping at idle if i rev it up to 4k or so. I know it doesnt sound right but thats what its doing.
I know the car runs active knock control when not in boost, so does this mean the car will advance timing to the point it detects knock (pending the AM) then retard when it picks up pinging? if this is the case my car must not be picking up anything?

I fitted a knocklink as well with separate sensor, and on the most sensitive setting will light up all the way when under boost, but not when i rev the motor up under low load ( i.e. no boost) and make it ping.

Not sure if this is relevant but i had to helicoil the knock sensor bolt hole cause i stripped it. Knock sensor is torqued to book specs.

This has got me baffled any help would greatly be appreciated.
before anyone suggests im heraring a heatshield or something else rattling...im not, i know what im hearing and its got me baffled. Ive run a hose to the block and plugged it in my ear and its definitely comming from the block.

Confused :-(

The rookie

iTrader: (1)

PinKing, not pinging! PinK not ping!!!!!

The correct mounting of the knock sensor base flush to the block is incredably (in the proper sense of the word) critical, is it possible its stood off by the helicoil, in which case, regardless of torque it won't work.

Thas the only thing in what you say that makes sense, its clear the closed loop knock control isn't working, there is only the one sensor, so....

Simon

sti146

Thanks for the correction in terminology.
But even if i was out a small amount with the helicoil...the base would still sit flush and the bolt head bear slightly to one side.
Any suggestions in this respect?

Thanks for the input..i was thinking that also but, my logic points me to the above conclusion???

Cheers