an idea for knock detection for matt

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chris2712au
 

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an idea for knock detection for matt

Post by chris2712au »

would it be easy enough to put an a condition that can monitor the actual timing and compare that against the timing in the maps so that if they are not equal then knock is detected.. and if they are equal everything is ok ?

that way you would not have to worry about the knock count stuff.. and you could set an alarm.. so when map isnt equal to actual and highlight the first cell that is in question ?
Eric
 

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Re: an idea for knock detection for matt

Post by Eric »

perhaps an even easier option would be to monitor the byte that contains the 'safe-mode'-flag
Most Nissan ECU's have this byte/flag

Eg. for the Z32 the flag is in register 0x82 (bit 7 or AND#80)
once the flag is set, it means knock was detected and it's using the safety maps

-Eric
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Re: an idea for knock detection for matt

Post by Matt »

Good news is that I report those safe mode flags in some of the ECUs already (including Z32 and R32). I'm doing the map switching updates at the moment to use those flags correctly
PL
 

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Re: an idea for knock detection for matt

Post by PL »

That'd be a very good thing to have. I got caught out again only last week with an R34 running off the knock maps while I was trying to tune the bugger. Grrrr!

Please make it a really obvious indication so I can't miss it! :)

PL
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Re: an idea for knock detection for matt

Post by Matt »

maps used at any time are light red so you wont miss it!
PL
 

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Re: an idea for knock detection for matt

Post by PL »

Noice! I've been caught so many times now....

Which vehicle families have this working now?

PL
chris2712au
 

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Re: an idea for knock detection for matt

Post by chris2712au »

yeah i guess the knock flag would be cool but what I am thinking would be ultra cool would be to have the alarm page set up so you can set alarm conditions.. like

alarm if TPS voltage < 0.5volts.. indicating a wire break..
or boost = 1bar and o2 > 12.0 AFR
or AFM voltage < 0.1 volts
or actual timing <>= main timing..
or temp > 80deg
or duty cycle > 100%..
or tps idle and etc you get the idea..

you do some of this with the delta compare.. but would be nice to have it for alarm.. I know that you can set the needle stops but sometimes like afr.. it is hard to minitor when you only want it to look in a certain conditions.. like if the enngine isnt warm you may not want to look at duty cycle.. and to be able to save the conditions in some sought of filter.. like favourites..

it really beats looking at log files searching for that condition especially when it may not have the resolution to do so..
chris2712au
 

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Re: an idea for knock detection for matt

Post by chris2712au »

you could even use them as trigger conditions for starting recording.. like if a certain condition happens start recording and if that condition goes away stop recording.. makes for an easier view of log files without going through an hour of log file..
chris2712au
 

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Re: an idea for knock detection for matt

Post by chris2712au »

on another note I have an indiactor on the boost control solenoid and I am using knock maps set to 255 and main maps set to zero.. so when ecu accesses the knock boost maps the light comes on.. kind of simple seems to work ok but I als think it is switching for other reasons other than knock.. maybe they are failsafe maps as well..
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Re: an idea for knock detection for matt

Post by Matt »

PL - should work for most vehicles once I add all the table entries in and test them (takes time to go through all the vehicles). nothing in current version (disabled)

Knock warning panel lets you set limits already (temp, inj pulsewidth etc can be selected here)
chris2712au
 

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Re: an idea for knock detection for matt

Post by chris2712au »

how long till we get the s15 code.. cause I know my knock sensor is playing silly buggers would love to try it out..
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Re: an idea for knock detection for matt

Post by PL »

Yeah, the alarms feature in the Knock Warning panel works great. I use this when tuning - not for monitoring knock but just for keeping an eye on other sensor values.

Just go to Operations, Knock Warning panel and then setup whatever paramters you want from the drop-down menu. It only looks at currently active paramters, so you need to be connected to your ECU with car running.

I use this to monitor coolant temp while on the dyno. Set the alarm at 95 degrees C. Once it reaches that value the text colour goes from green to red. The font is huge so it's hard to miss.

I guess you could also use this in a similar way for monitoring injector duty cycle too.

PL
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Re: an idea for knock detection for matt

Post by Matt »

Chris will have to wait a bit. I've got 60 entries in the ECU list to add and test :(
Topdog781
 

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Re: an idea for knock detection for matt

Post by Topdog781 »

PL wrote:Yeah, the alarms feature in the Knock Warning panel works great. I use this when tuning - not for monitoring knock but just for keeping an eye on other sensor values.

I use this to monitor coolant temp while on the dyno. Set the alarm at 95 degrees C. Once it reaches that value the text colour goes from green to red. The font is huge so it's hard to miss.

I guess you could also use this in a similar way for monitoring injector duty cycle too.

PL
It would be pretty cool if you could preset one of your dash board lights so they light up if the engine was knocking or to have a feature that automatically shuts down the car if the engine reaches condition past your safety presets...these are all features with dsm link and are reasons why it dominates the dsm world.
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