News:

New Users: Send [email protected] an email with your account name. I've turned off auto-approve to reduce the 100 new spam accounts a day. Thanks, -Jason

Main Menu

tests for knock sensor

Started by multiplex, March 23, 2008, 07:31:48 PM

Previous topic - Next topic

Sprocket

Quote from: multiplex on March 25, 2008, 10:45:39 PM
ok so maybe i was able to answer some of my own questions.

doesn't look like this is how megatune sets the values. i'll have to head back to the garage and try this out

From firmware page, reference 1.1.26

knock_chan=F0 disables knock. Other values select bank individually for each ignition event (practical for V8, V6, I6 and even I5 where there are more than 1 knock sensors).
    * knock_chan=00 selects knock channel 0 for all ignition entries
    * knock_chan=FF selects knock channel 1 for all ignition entries
    * knock_chan=AA selects knock channel 1 for every other ignition entries. Bit7 is for entry0 (belongs to the topmost entry in the MegaTune ignition output and reftooth tables). 0x55 is obviously the inverse, bit7=0 so the sensor belonging to the cyl fired by the topmost ignition entry must be connected to knoch channel 0 (the only knock channel normally).

a little confusing, but it looks like just what i need


If i understand this correctly, from what Rob said a while ago regarding the knock channel numbering. knock_chan=00 selects knock channel 0 for all ignition entries, only one sensor is in use and samples each knock window. If knock_chan=FF selects knock channel 1 for all ignition entries, would suggest two knock sensors are in use and both simuntainiusly sample each knock window. knock_chan=AA selects knock channel 1 for every other ignition entries, would suggest two knock sensors are in use but, one on each head of a V8, V6 or flat 4 and each knock window is sampled by each sensor alternately as per the ignition sequence in h[2] table

??

[email protected]

Thats pretty much as I understand it.  With a straight 6 I think the pattern will be different again as some I've seen have two sensors for three cylinders.

billman

#17
Nice infos guys, but i dont get even the half of it. Could you please tell me if there are any settings for the for the Audi I5 that we could use in MT? My MT shows Channel 0 and channel 1. Nothing else.

multiplex

with the current config file for megatune, you can't directly set the proper knock value. You will either need to use the terminal console, or the keyboard and LCD display.  Hopefully that will be fixed soon. wish i knew how to edit it to that extreme

So your motor has two knock sensors?

Where are they located? Or which cylinders do they cover?

if your firing order is  1-2-4-5-3

Assuming Sensor 1 covered 1,2,3  and sensor 2 covered 4,5

your config in binary would be

0 0 1 1 0 [ 0 0 0]   The last three bits don't matter as they don't represent actual cylinders

So changing this into Hex it would be 30h, or in decimal 48

Hope that helps!

billman

#19
Can you plase give me exact instruction on what to write in the terminal. I dont have Keyboard and LCD either and i dont know the commands for terminal. Where should i give the the hex or decimal values?

GintsK

In fact I5 firing order is 5-3-1-2-4. because first spark after trigger becomes in 5th cylinder.
                                1-0-0-0-1-0-0-0 in theory must work.

Disappointing aspect is Megatunes incompatibility.





billman

what command should i use in terminal so i can get the knock to work. I dont know nothing about terminal commands.

Sorry for my ignorance and thanks for your help.

[email protected]

I don't know that you have to use Terminal to configure the knock setup, MT should do it fine.

billman

These are the settings i have now but they doesnt seem to work:



[email protected]

So you're getting detonation but not seeing any retardation?

billman

No, i hit the engine and the sensor with a tool and got almost no knock diff.

billman

Is there any new infos on how to set the knock sensors up on the Audi I5 engine? Still dont know what to give on the terminal or what values to put in the config files.

Denmark

This is so complex that it seems that no one can use it, so i think itÃ,´s junk, so just skip it,

as i have said earlyÃ,´er i have a knocklink mounted on my car, and itÃ,´s showing the big red led, anytime there is knock, this is a really simple device, the only thing that can be changed is the volume on the "noise", that it detects,

I belive for anyone to have any use of the knock settings, it need to be as simple as that,
on a Link ECU that is just the knockthreshold that needs to be definded,
Meaning that on a scale from 0-255, you deside when ever there is knock, and it will then take action, and retard....

also like this....

http://aztecperformance.co.uk/gizzmo_shift_light_dual_stage.aspx

http://www.linkecu.com/products/AncillaryDevices/KnockLink



/Skassa
working on the boxer

[email protected]

It's complex, but there are many that use it, and its certainly not junk.
dnb has been doing a lot of work on the knock sensor and has had some good results from what I've seen.  It did require a change to the values in the vemsv3.ini file.

Rob

dnb

As Rob says, I have been getting half-sensible readings of knock on my TVR.  What you need to do is tweak the vems_v3.ini file so that it can report the "knock_signal" and "knock_noise" parameters.

The one you're interested in is the signal - the noise is just an estimate of the background, and it's mostly contamintated with other cylinders, (at least in my case!) so I ignore it. 

Once you have the signal parameter being logged, then you have the equivilent of a knock link.

The next stage hasn't happened yet - my young daughter consumes what used to be my programming time at night ;)