knock sensor replacement option

[ska69]

Hi everyone,

Is it possible to replace the stock ca18det 1 wire knock sensor with a 2 wire knock sensor of this style:




Such style knock sensor is used in SR20DET, SR20DE, VG30DE and VG30DETT and many of other engine from various manufacturers, I also happen to have a new sensor with a new pigtail to it, that's the main reason for installing it instead of the stock sensor. Wiring-wise and ecu-wise, I don't really care, as I'm prepping the engine for megasquirt.

any help appreciated

[float_6969]

I would doubt it, but you could look at the diagnostic info for both sensors in the FSM's and see if the specs are the same.

[ska69]

I sure will look into that, however it looks like an ordinary bosch style knock sensor, my concern is about fitting it to the block in place of the stock sensor.

[blownhemi]

I sure will look into that, however it looks like an ordinary bosch style knock sensor, my concern is about fitting it to the block in place of the stock sensor.

KA24DE's have the same sensor attached to the block with just a bolt through it. I don't see why it wouldn't work, if you're not using the factory ECU anyway.

[ska69]

yep, ka24de has this style. Hope it'll work, haven't had a chance to test fit it, it's just that from the pictures I found online, the CA18 has a less contact area between the block and the sensor, however not sure if it matters hence the sensor reacts to the frequency through the connecting bolt.

[float_6969]

You can just put a bolt through it and it will be fine. The sound is transmitted through the bolt. My concern would be in a difference in resistance values or frequency sensitivity causing it not to function properly.

[ska69]

thanks for confirming that. Regarding the difference in resistance, as it's intended to be used with Megasquirt, a small black box from these guys http://www.viatrack.ca/ should help out.

From what I've read, any knock sensor cannot directly talk to MS, some sort of encoder is required. I'll follow up on this once I come across any other info.

[louiswun]

The round shape knock sensor is wideband type (non resonant knock sensor), it will pick up wide range of engine noise including knock, it require the ECU to do the filtering job, set up for identify knock frequency out of the engine noise, and the knock frequency is refer to the bore size. This type of sensor can be use on wide range of engine.
But it cannot/should not replace the CA18 stock knock sensor, CA18 is equip with a resonate type narrow band knock sensor, this type of sensor is only sensitive to specific knock frequency, if replace with a wideband type knock sensor, the CA18 ECU will also pick up the noise not just the knock.

[TheMAN]

interesting... louis...
that sensor is used by the J&S safeguard too... which is designed to supplement the stock system, not replace it

[float_6969]

That is interesting information. I didn't know there were 2 different types of knock sensors! Learn something new every day.

[TheMAN]

well there you go... we now know the stock knock sensor is inadequate when significant mods or higher boost is used

[ska69]

yep, I agree with you Louis...but my question was about fitment of a bosch type sensor inplace of the stock sensor. Because I want to run Megasquirt in the future which can interface with such sensor type via a decoder box.

[TheMAN]

if you get rid of all the stock engine management, you can run whatever sensors you want!

[ska69]

I kinda figured that out too...
provided such knock sensor type is physically compatible with the block w/o heavy modifications; which is what question was about.