where is the knock sensor located? on 1990 Oldsmobile 88

I am trying to replave the knock sensor do to a code 42 but i can not find it anywhere. please help

2 answers 1 comment
location of knock sensor is one of two places. It screws into the side of the engine block and best to look for it from under the engine to visually see it. It screws into the side of the engine block at the mid-point length of the block.
It's located on the left side of the engine. look at the
I'm not sure where it is, but here is a pic of the knock sensor, this might help you to identify the sensor: http://www.rockauto.com/catalog/raframecatalog.php?carcode=1215324&parttype=5108
Here is the code info too: http://repairpal.com/gm-code-42