Re: Testing Knock Sensors

[Orin Eman <orin@wolfenet.com>]

Yes, but whatever signal the sensor produces is ignored below 0.7bar.
As long as there aren't any major vacuum leaks, it isn't going
to affect timing at idle.

> That's when the ecu turns the regulation system on. That doesn't mean that
> the piezoelectric crystal in the sensor isn't conducting. On the contrary,
> it still is. An o2 sensor will still function even when the system is in
> open loop.

> ****************************************************************************
> *Steve                                             Sachelle Babbar
> *'87  5000CS Turbo 5spd 1.3-2.0 bar             <SBABBAR@IRIS.NYIT.EDU>
> *Cockpit adjustable wastegate, AudiSport badge
> *
> *Disclaimer:"Any information contained herein is based purely on my own
> *personal experience and may not necessarily reflect yours. Use caution as
> *your results may vary from mine."
> ********************************************************************************




> On Thu, 2 Dec 1999, Orin Eman wrote:

> > > you also should be able to watch the flywheel with a timing light, as
> > > your talented assistant taps the block (or the sensor - but with
> > > something light like a thin screwdriver - very lightly!), you will see
> > > the timing get retarded as the ECU "hears" the knocks you are making and
> > > takes corrective measures.
> > 
> > Probably won't work.  The ECU knock code only takes effect
> > over 0.7 bar manifold pressure.
> > 
> > Orin.
> >