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Knock sensors and Elite 2500


Tobz
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Hey all,

Im finding it hard to determine this for sure. What I would like to know is if the elite 2500 uses the factory Nissan knock sensors at all? 

Just asking as the wiring for the front knock sensor just got split and it's a pain to get in there and fix. So figured if it's not being used, why bother?

Thanks for the help!

Toby

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It can, however if you have no knock strategies setup it does nothing.

For the Kebabtech to do anything you need to firstly enable them and have some form of igntion retard and/or fuel enrichment setup. By default, IIRC nothing is setup.

You could simply just press F4, search for knock sensor and untick the box and forget they're even connected.

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So walked away from it and tried to get to the sensor connector again just then. Its amazing how something that seemed so  impossible before was so easy! Just didn't have my hand in the right place. Went back when fresh and got it off in a few seconds. 

Ordered a new connector as the existing one has gotten super brittle, and it's not overly expensive. So easy fix in the end

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I would definitely run the knock sensors especially if you’re pushing the performance envelope that most of us are.  If you’re running decent boost and advanced timing I think it’s asking for trouble to not have some engine protection built in around a knock threshold.

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  • 2 weeks later...

So I had a look in the ECU, there was no knock protection in place. 

I also watched a lot of youtube to get a base understanding of how the Haltech worked. Started to get concerned with how my car was setup and there was minimal engine protection. 

Then I also realised some basic things were not setup correct, such as the flex fuel sensor not being enabled when i supposedly got a flex tune done.... 

Also the IAT sensor was put wired into the SPI input and not the AVI, they then did an odd calibration based on this which made it look sort of correct on the dash, but was actually way off..  

VCT was not being used.... 

Self Learning Fuel Trims were setup to only activate if the coolant temp was above 90c.....

God knows what else was wrong as i obviously have a very limited knowledge of the ECU.... literally based on a few HP Academy videos... 

I mean if I could find these issues after what could be considered 2 hours of youtube...  how on earth can a "professional" who works at a well known shop here get it so wrong?

To say I'm p!ssed is an understatement.... Anyway its at a more reputable place now getting rectified... Turns out this new place has seen a lot of issues from the old place... so its fairly common from them, unfortunately....

Edited by Tobz
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On 9/21/2021 at 5:49 PM, Tobz said:

So I had a look in the ECU, there was no knock protection in place. 

I also watched a lot of youtube to get a base understanding of how the Haltech worked. Started to get concerned with how my car was setup and there was minimal engine protection. 

Then I also realised some basic things were not setup correct, such as the flex fuel sensor not being enabled when i supposedly got a flex tune done.... 

Also the IAT sensor was put wired into the SPI input and not the AVI, they then did an odd calibration based on this which made it look sort of correct on the dash, but was actually way off..  

VCT was not being used.... 

Self Learning Fuel Trims were setup to only activate if the coolant temp was above 90c.....

God knows what else was wrong as i obviously have a very limited knowledge of the ECU.... literally based on a few HP Academy videos... 

I mean if I could find these issues after what could be considered 2 hours of youtube...  how on earth can a "professional" who works at a well known shop here get it so wrong?

To say I'm p!ssed is an understatement.... Anyway its at a more reputable place now getting rectified... Turns out this new place has seen a lot of issues from the old place... so its fairly common from them, unfortunately....

The reality is that good powertrain calibration engineers can land well-paying jobs at the OEMs and not deal with customers or customer service, so the tuners that most people can access on the open market are usually not the greatest. The consumers of tuning usually have no idea how to check stuff like this either so unless the tune is bad enough to break engines (not uncommon) there's no real verification.

I've basically accepted at this point I need to just DIY my tune. I don't like the idea of this but that's just how it goes. Maybe if I ever get my base map to a good state I'll post it up somewhere as open source.

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Whoops sorry, totally missed this thread.

If it's not setup you won't see it enabled - easiest way is to hit F4 then go into Functions, then search for it. It would be under Knock Control (knock detection needs to be enabled first). Once enabled you will see it appear up in the functions list.

Using a knock calculator, such as this one for a stock motor the ~ frequency is 6700kHz for a slighter bigger bore 6600kHz (of course this is an implied frequency based on the diameter of the piston (doesn't factor in recessed areas, etc.)

https://phormula.com/knock-frequency-calculator/

image.thumb.png.8a9cc94b32b46ba262e97c2a1b512fc8.png

 

Also, there's nothing wrong with using an SPI for temperature, it works perfectly fine provided you have the correct sensor data loaded up. I have mine like this (just because I ran out of inputs lol)

image.thumb.png.93e7be3375d708118d7aee1a67641d9e.png

image.thumb.png.a38e0012382bbc94ffdc82b54b82a084.png

Yes, plenty of workshops don't bother with the small nitty gritty - they just focus on the dyno graph and the peak power.

Also, there's a high chance that "professional" just used a working map from a GT-R to use on your car, at the same time forgetting to enable VCT, etc.

No one ever starts from "scratch" as they say. When I tune cars for mates, I always tell them upfront I will be using XYZ map I made before for ABC car.

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Also I can nearly guarantee you 9 our of 10 workshops never bother to fully dial in the fuel density table. I got this data from interpolating BP 98 data and ethanol density from an EVO forum. Sure it might not be accurate but it's better than having the same fuel density across the board for ethanol percentage and temperature.

Feel free to copy, however please note if your car as been tuned around a static fuel density, adding this in will affect your tune!

image.thumb.png.2eeee0375b5bdc71882d661db48fb193.png

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I think if it was thing that was a bit... o that seems odd, i would be ok, but it was so many things.... just lost faith...

 

On 22/09/2021 at 11:03 AM, Dose Pipe Sutututu said:

Whoops sorry, totally missed this thread

Thanks for this :) nothing was in place.. which i totally understand as from what i read they can be very finicky to setup

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On 22/09/2021 at 11:05 AM, Dose Pipe Sutututu said:

Also I can nearly guarantee you 9 our of 10 workshops never bother to fully dial in the fuel density table. I got this data from interpolating BP 98 data and ethanol density from an EVO forum. Sure it might not be accurate but it's better than having the same fuel density across the board for ethanol percentage and temperature.

Feel free to copy, however please note if your car as been tuned around a static fuel density, adding this in will affect your tune!

image.thumb.png.2eeee0375b5bdc71882d661db48fb193.png

What was interesting is the car was setup to run the same timing for e85 and 98

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On 11/09/2021 at 10:08 PM, Shoota_77 said:

I would definitely run the knock sensors especially if you’re pushing the performance envelope that most of us are.  If you’re running decent boost and advanced timing I think it’s asking for trouble to not have some engine protection built in around a knock threshold.

If you're runinng E85 however, you really need to cock it up big time to register any form of knock. Put it this way, if you ever manage to generate any kind of knock on E85 then you have bigger problems!

On E85 you could keep pumping in timing, literally fall face down with power and still it won't knock! Going past MBT and the motor will be fine (I'm a bit guilty of this, I will add timing till I see a loss in power and i know it's good to stop LOLOLOL)

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On 22/09/2021 at 11:08 AM, Tobz said:

What was interesting is the car was setup to run the same timing for e85 and 98

it might be hidden in a 3rd dimension somewhere, I generally just use the compensation table to do E85 

How I like to do it, however MoTec guys like to use a 3rd dimension in their main ignition table

image.thumb.png.9dbabfcf32c728fc2b304afe9b45683a.png

 

How MoTec tuners like to do it (note the slider at the bottom), also what you see there is my 98 map, although the slider is dragged to E80 - it's because I use the compensation tables instead 
image.thumb.png.25130d91089b3ef59d5dfe5810a15af0.png

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That's interesting...  although meant nothing as the flex fuel sensor in my car was disabled... I did ask them a few times why my dash would always say 85% ethanol even when i had 98 in it.... and enquired why my AFR was 8:1 when on 98... was told not to worry and its all fine... seemed very odd to me though

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On 22/09/2021 at 11:16 AM, Tobz said:

That's interesting...  although meant nothing as the flex fuel sensor in my car was disabled... I did ask them a few times why my dash would always say 85% ethanol even when i had 98 in it.... and enquired why my AFR was 8:1 when on 98... was told not to worry and its all fine... seemed very odd to me though

LOL... jesus...

Yeah not having the flex sensor is just like having a straight E85 tune and pouring in 98. Great way to wash the bores and foul your plugs.

Too bad you're not from the hood - would happily show you things in person on the dyno.

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