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Old 25-11-2017, 11:46 PM
jondee86 jondee86 is offline
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Join Date: Dec 2015
Location: New Zealand
Posts: 78
Wink Re: Nozzle spray angle...

I have the factory knock sensor connected to my ECU and there is a
headphone jack on the ECU so I can listen directly to the knock signal. The
problem is that the engine is mechanically noisy and the s/c also makes gear
"rattle" noise in the same frequency band as the calculated engine knock
frequency. The knock signal is high at idle, at low rpm's and on deceleration
even when fuel cut is active.

At high rpm's the knock signal reduces to nearly zero, but when throttle is
reduced and the s/c gears become unloaded, the knock signal instantly
becomes high no matter what rpm's. So I need to be able to program the
background knock threshold levels, and discriminate between mechanical
noise and real knock.

Some of the high end knock monitoring can do most of this, like the PLEX
unit. Only it is a very expensive experiment if it does not work effectively !!

I have been considering trying a Bosch "donut" sensor in place of the
factory sensor, and locating it to a diffrent mounting position. Maybe that
will provide a better signal as I read that the wideband type of knock sensor
is sometimes more effective than the factory tuned type.

The knock light shown in your link is cheap enough to experiment with. But
this locally made product might be a better option...


http://www.nzefi.com/product/knockli...ation-warning/

A visual indication is probably the best option for me, as I will have to make
my own decision if it is knock or noise according to how I am driving at the
time the light comes on. Will have to decide on this soon

Cheers... jondee86
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