code 2141 knock 'regulator?'

[Orin Eman]

> Today, under very light boost in 3rd gear I got the check engine light
> and dumped the codes and got the 2141 which I looked up to be the knock
> regulator.  Did not notice any loss of power.  I tried to get reproduce
> the situation (3rd gear, accelerating up a hill) that gave the warning
> in the first place but could not get it again.  I always, always only
> use Chevron Super Supreme 94 octane.  SJM site says fuel octane too low,
> excessive compression, excessive boost as causes.  I listened to the
> engine and did not hear anything out of the 'ordinary'.

I doubt you would be able to hear anything...  It takes rampant overboost
to actually hear any knock.
 
> Any ideas what might cause this code?  Are there any usual suspects? It
> is the first time since owning the car that I have got this code (2.5
> years)

It could be the knock sensor.  Make sure it hasn't shaken loose.
Unfortunately, the only real way to tell is to swap it with a
known good one.

It could also be a slightly mis-adusted hall sensor.  There is a bug
in the MAC11 ECUs that can cause them to lose track of the cylinder
number if the hall sensor signal doesn't occur at the right time.
This is highly unlikely though.

Unless it happens again, I wouldn't worry about it...  My car once
threw a knock sensor code too.  Can't remember why and it doesn't
seem to have returned.

Orin.