Knock questions

[Dave_GSR1.8]

Ok, I have gone through a heap of posts that mention knock and from those (and my current issues) I have a few questions;

- how much knock is acceptable, if any ?
- how much does oil vapour in intake affect knock?
- is there a better knock sensor than OEM for Lancer cc GSR 4g93T ?
- what is the service life for a OEM knock sensor ?

Many thanks for any responses.

 

[CYBORG-X]

Is this for ecmlink.?

 

[Dave_GSR1.8]

Also, in an old post from

http://www.4gtuner.com/topic/19889-check-engine-light/

in post 4,

blackvr said:

"With the knock sensor, I can view the activity on the ECM datalogging. Even with a properly working sensor, you would be very surprised at how active they are, especially when its obvious there is no knock happening !! Its pretty common with built motors and big exhausts."

So, more queries !

1) Are the knock sensors overly sensitive, giving lots of false +ves with big (3") exhausts, in cc GSR's?
2) How do you tell from an ECMlite v3 log that "there is no knock happening" when the log is showing knock?

 

[Dave_GSR1.8]

Yes, running ECMLink EVO1-3 v3lite

 

[CYBORG-X]

From memory, 1.4deg knockretard is acceptable limit. It works out being 3 knocks per something..

 

[Dave_GSR1.8]

Hmm, then I am still in a bad place, getting anything up to 6 degree knock retard (well at least a logged value in ECMlink)

 

[4piknup]

A couple of points is ok. But better if none as it allows for a crappy tank of juice or a hotter day or whatever...

oil in intake will dilute and lower the octane of the intake charge, and make knock come on earlier.

ignore knock below 3k rpm. And to check for false knock, try some better fuel or octane booster and retry. Your knock should reduce if it is real knock.

 

[4piknup]

Feel free to change up to a new cc knock sensor, they can and do go bad. There is no better option than the oem replacement. A late evo sensor may be compatible. I think it is the 1g sensors that are different.

 

[Dave_GSR1.8]

Gents, thanks for the feedback.

Always put 98 octane in it, I may have to put some catch cans in though, as oil burn is a problem on overrun (crappy engine or crappy turbo, can't pinpoint cause, motor has only done 80,000 kms since light bottom end rebuild and head was only done 6 months ago). I don't care any more as one day when I am rich I will forge it or convert it. In the meantime I'll just keep an eye on the oil level, its cheaper.

I have started to hunt down a new knock sensor, but it is proving a little more elusive than I thought. Does anyone know if EVO ones are compatible ?

 

[4piknup]

I sure the vr4 ones are not compatible.
I think the evo ones are ok for you. One of the other guys is sure to know.

why dont you pull a few degrees timing and see if it reduces knock.
what rpm is your knock, what boost is it at, how much knock and what timing?
I have 3in exhaust, and other bits, and very little logged knock retard.

You dont have the 1g ignition table do you? Cause that may be why.
Is your base timing 5°?

 

[khubner1]

evo/gsr are the same. ran a gsr knock sensor on an evo ecu no issues. just don't put one from a 4g92 on it i know those arn't compatible