Replacing Knock Sensors

Kent McLean kentmclean at
Fri Jan 6 09:37:24 EST 2006

Peter Schulz wrote:
> Need to replace a pair of knock sensors on one of the 3B wagons...
> Family Album shows a blue sensor  054905377A  and a brown one 077 905 377A
> The brown one cost 2x the blue there a difference or can the 
> blue one be used in both the front and rear locations?

I haven't seen a reply to this, so I'll give you my thoughts.
The V8 has a pair of sensors, the ignition reference sensor
and engine speed (RPM) sensor, that are functionally the same,
but they are physically different -- one is blue, the other
is black. They black one is NLA, so people substitute the blue
one. They also substitute one from the 5000, as it it cheaper.

I suspect your knock sensors may be functionally the same,
but one has longer wires, hence the different part numbers.
But that is just a guess.  Try it and let us know. :)

Kent McLean
'94 100 S Avant, "Moody"
'89 200 TQ, "Bad Puppy" up in smoke

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