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Continuing on from a high jacked thread.

 

Remember this is a forrum not a wiki fact even though I'd love any responses with some hard cold facts.

 

How do the knock sensors work exactly with the ecu.

 

I know they are a Mic type sensor , the ecu can't here sound though, so it converts it to frequency (voltage).

I am sure I've read about as well as witnessed with my rb20det the ecu changes knock voltage resistance in 9rder to detect knock levels.

 

I had my car on 98 octane knock voltage was 2.4v.

 

Put in e85 (I am flexi o2 sensor setup)

Knock voltage takes steps over time at idle to 2.1

 

What I read is that it does this because it gets minimal knock counts and increases the Mic power by lowering the voltage resistance.

 

In a wave graph form 2.4 up then down , a listening spike of knock of .0333 of a volt or what ever miniscule amount will be smaller in that (2.4) than in the (2.1).

Making it easier to recognise knock.

 

Ok all you cheeky buggers that wanna tare at me as if I changed a bible.

 

Your turn to swing [emoji8][emoji23]

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15 minutes ago, Slap said:

 

Continuing on from a high jacked thread.

 

Remember this is a forrum not a wiki fact even though I'd love any responses with some hard cold facts.

 

How do the knock sensors work exactly with the ecu.

 

I know they are a Mic type sensor , the ecu can't here sound though, so it converts it to frequency (voltage).

I am sure I've read about as well as witnessed with my rb20det the ecu changes knock voltage resistance in 9rder to detect knock levels.

 

I had my car on 98 octane knock voltage was 2.4v.

 

Put in e85 (I am flexi o2 sensor setup)

Knock voltage takes steps over time at idle to 2.1

 

What I read is that it does this because it gets minimal knock counts and increases the Mic power by lowering the voltage resistance.

 

In a wave graph form 2.4 up then down , a listening spike of knock of .0333 of a volt or what ever miniscule amount will be smaller in that (2.4) than in the (2.1).

Making it easier to recognise knock.

 

Ok all you cheeky buggers that wanna tare at me as if I changed a bible.

 

Your turn to swing emoji8.pngemoji23.png

 

What?

 

 

In particular seeing as you ha and asked for fact sheets when people have pointed out what you have said is wrong, seeing as you read this

 

"What I read is that it does this because it gets minimal knock counts and increases the Mic power by lowering the voltage resistance."

 

can you start with where you read that from?

 

 

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I have been looking and for other stuff too.
I believe it was a tunning forrum.
It was 5 years ago when I was goin nuts trying to figure a way to analogue tune my car with the dodgy safc.

Before I read that I just believed the voltage readings were the figure the ecu used.

I will do my best to find it but reality is. Saying 'wtf' isn't a real post or help or discussion.

As I stated in the high jacked thread you guys were making me believe. Not vice versa.
All I did was attempt to help someone and have most my posts miss quoted or misunderstood. If it was understood I would have reasonable responses posted back to me.
I see some attempts at this without the extra expanded thought. Like the impacts of the 'explained' vs what I said , and yes maybe I am wrong on some levels or maybe not why I started the thread.

I actually see why no one comes to sau anymore unless they desperatley need help.
It's like a farkin clergy.
Can't say one thing wrong or in the wrong way or ya get molested by the elders. Ahahahahahahahahaha.

Common good discussion. Not prove it.

I wanna hear from people that have analogue tunned there car by fooling.

Yes everyone with a pc that tinkers too.

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As I said my phone wants to correct me yep I'm a bad speller but I don't care.
Also have fat thumbs.

So I agree u will understand that.

Don't be a keyboard warrior.

That's like paying too much for nuts.
Bahaha (hey I didn't make shot postage was 8 bucks and I had to drive there to post about 5 bucks.)

Spelling is the least of my worries.
It's the egos that float about here.
I am human.
Some respect goes a long way.
Show me yours and I show ya mine.

Always been an issue here at sau though.

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I found some knock sensor info I'd like to share. It's not the article i read about the rb20det ecu. But will be helpfull to some people.

Note that this isn't all car specific.

https://www-azosensors-com.cdn.ampproject.org/v/s/www.azosensors.com/amp/article.aspx?amp_js_v=a2&amp_gsa=1&ArticleID=50&usqp=mq331AQCCAE%3D#referrer=https%3A%2F%2Fwww.google.com&amp_tf=From%20%251%24s&ampshare=https%3A%2F%2Fwww.azosensors.com%2Farticle.aspx%3FArticleID%3D50


https://carfromjapan-com.cdn.ampproject.org/v/s/carfromjapan.com/article/car-maintenance/knock-sensor-work/amp/?amp_js_v=a2&amp_gsa=1&usqp=mq331AQCCAE%3D#referrer=https%3A%2F%2Fwww.google.com&amp_tf=From%20%251%24s&ampshare=https%3A%2F%2Fcarfromjapan.com%2Farticle%2Fcar-maintenance%2Fknock-sensor-work%2F

This was a good read too.

https://www.eevblog.com/forum/beginners/testing-the-frequency-response-of-a-knock-sensor/

What i was talking about is the engine noise voltage resistance. So it only hears the knock.
That is the resistance that I remember reading about that the ecu modifies to help listen. I'm pretty sure.

Also might be worth noting that my experience here is with the 20det ecu. Maybe the 25 is diff. I'll keep googling. Try to find the article from years ago.

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Me looking at google aint what a discussion is. You were full of insight earlier and i take aboard what you said why im wanting a discussion. The bit about the belt making the rb jumpy cause of cas not crank sensor was on the money, I'm wondering is they are different in the way the ecu interprets and gathers information from the knock sensor.

Surely somone can show me a tuning article where it says the appropriate confirmation of how the ecu interprets and deals with the knock frequency vs the noise frequency.

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SAFC tuning is just as good as advancing your CAS a few degrees and bumping up the fuel pressure. As you bend your AFM signal you're using different a TP Load column. Great for grenading motors if you're not careful.

Stock ECU belongs in the bin, only exception is when you've installed a Nistune board. If you need a Nistune for it, I'm a dealer and also tune them. 

PM me for pricing.

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Firstly this has been moved from for sale to a more appropriate section.

Second, I'm not really sure what the question is, or your intended action based on the response, but page EN-229 of the GTR workshop manual talks about the knock sensors and how they work.  One thing you should be aware is they do not detect knock, just a sound that is likely to be knock

 

 

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9 hours ago, Slap said:

ecu interprets and gathers information from the knock sensor

ECU doesn't really give a shit unless it exceeds a threshold and just pulls out timing, nothing more nothing less.

It's not as advanced as modern ECUs, it's 1980/90s junk at best. Unlike an EVO ECU, it actually run multiple maps for low/high octane

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Does not seem like a discussion.
More like a scolding.
pfft to this site and to you egotistical
Karnts.
I cbf talking to you as you haven't backed anything up just talk to me like I'm nothing.
Maybe id listen to you idiots if you had some respect. Besides who the fark are you. Some jerk off that can't even have a discussion on the net without belittling somone else too feel better.

f*k u * looks at (gts boy)
f*k u *finger too (dose pipe stustustut
f*k u *jerk off motion at(ben c)
Ur kool *points too (duncan)
I'm out

[emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji867][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959][emoji2959]

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Lol... how many cars have you popped on the dyno and tuned yourself?  

Yeah not many.

Also the duct tape on your BOV return isn't doing you many favours either.

I'm all happy to help people and give them some information  but you've come across as some yoda, nearly like a Andrew Hawkins with a RS3 kind of guy.

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didn't seem that way
Yeah I worded it wrong.
And surprise surprise y'all prove me right about not being able to discuss shid respectively . Ahaha.

IF YOUR SMART ENOUGH TO TUNE.
YOU SHOULD BE SMART ENOUGH TO UNDERSTAND ME.... AND NOT PROVE HOW MUCH OF A WANK PACK THIS FORRUM IS WITH THE ATTITUDE YOU GIVE.

As I stated I'm not wanting a discussion with anyone that thinks I should kiss there ass. Fark off.
Let people who want to actually discuss it do so.

Thread ruined. Locking the door on this one for me. Maybe someone that is interested in how the ecu works (not just gets tuned) will make a thread where I can have discussion without a pack of priests raping me over the sacrilege of my non beliefs in there bible.
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