I'm not a DIY'er, but I want to not throw money away at possible wrong
repairs.

1997 Legacy 2.2l

6 months ago my check engine light came on and the code read at Auto
Zone was "Knock Sensor" It was suggested that the part could be
faulty, could be a wiring short (intermittent). The check engine
light comes and goes. It almost always comes on after 1/2 hour or so
at highway speeds. I've never notice it go out while driving once it
comes on, but sometimes it's just off when I turn the car on again.
I've never heard knocking under heavy acceleration when the light is
on.

My question is whether that particular check engine code is prone to
indicating failure in a component which is incorrect, ie something
else is wrong (and whatr that might be). This sounds like around a
$200 mechanic repair (diag, part, labor). It's not a lot, but I'd
like not to have the same code pop up again after installing a new
part.

TIA

On Tue, 20 Mar 2007 21:29:57 -0500, kaplan3jiim wrote:

> I'm not a DIY'er, but I want to not throw money away at possible wrong
> repairs.
>
> 1997 Legacy 2.2l
>
> 6 months ago my check engine light came on and the code read at Auto
> Zone was "Knock Sensor" It was suggested that the part could be
> faulty, could be a wiring short (intermittent). The check engine
> light comes and goes. It almost always comes on after 1/2 hour or so
> at highway speeds. I've never notice it go out while driving once it
> comes on, but sometimes it's just off when I turn the car on again.
> I've never heard knocking under heavy acceleration when the light is
> on.
>
> My question is whether that particular check engine code is prone to
> indicating failure in a component which is incorrect, ie something
> else is wrong (and whatr that might be). This sounds like around a
> $200 mechanic repair (diag, part, labor). It's not a lot, but I'd
> like not to have the same code pop up again after installing a new
> part.
>
> TIA


Try high octane gas, if the light goes out, then the knock sensor is doing
its job by detecting the knock. If it does not go out, then it could be a
bad sensor or some other problem with the sensor. Or some other engine
component knocking and the sensor is legitimitely letting you know.