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Piers1989
27-02-2017, 12:26 AM
So I've spent some time tuning my car over the last couple of months, and switched to trying out KS2.0 a couple of weeks ago now I have my bearings with evoscan and ecuflash.

I am getting some wierd behaviour in relation to knock detection. I've set a map now and know it is selecting it correctly etc, but it keeps (on some runs not others) seeing knock around the same areas.
I've pulled timing to a few degrees below the stock and also set fuelling to STUPIDLY rich, and its still being detected.
I have the high octane map set to 8.9 AFR (and the low to 8.0 to be safe) in the relevant cells, and on my gauge its reading 9.7-10.1 AFR in practice, yet this knock persists.
Pushing around 1-1.1 bar boost.

I looked into how this works (Merlins guide 1.7a) and from what I see the knock SHOULD be logged when the filtered knock (Request 6A) is higher than the knockbase (Request 6B).
My Evoscan calls 6A Knock_adc_processed but understanding what the filtered knock is that sounds equivalent, and it's the same request ID so 99% sure its right.
I find that my processed (filtered) knock is NEVER anywhere near the knockbase.

I have attached a log showing a pull from low speed in second gear to near 7k rpm, then all the other gears until suddenly huge knock is detected in 5th and I back off.
You can see that even when the knock suddenly appears out of nowhere (bear in mind its multiplied by 10 for the graph).
I have attached a few snips snip of the graph functionality in evoscan to overlay the relevant information, but obviously feel free to dissect it yourself.
767317673076732


Does anyone have any ideas, as I'm pretty positive that I'm not destroying the engine as much as the logs would make out! I've literally set it to dump fuel! If anyone wants a copy of the ROM I can send that too.

Nick Mann
27-02-2017, 06:56 PM
I'm not any kind of expert so don't get hopeful of me helping! However, questions that spring to my mind:

Have you got measured AFRs?
Have you got a fuel cut defender?
Can you get the result in any gear?
What happens if you short shift on your run so you are in the 4000-5000rpm range in each gear?
Is the knock coinciding with road surface at all?

Piers1989
27-02-2017, 07:20 PM
I'm not any kind of expert so don't get hopeful of me helping! However, questions that spring to my mind:

Have you got measured AFRs?
Have you got a fuel cut defender?
Can you get the result in any gear?
What happens if you short shift on your run so you are in the 4000-5000rpm range in each gear?
Is the knock coinciding with road surface at all?

Thanks for the ideas Nick.

I have measured the AFRs, its around 10 (sometimes less) when the car suddenly thinks there is huge knock.
Fuel cut is removed
In that run, it happened as soon as I used 5th gear, but I believe I've seen it at similar RPM in 4th too previously.
I haven't tried a run short shifting and logging, I will try that.
I've used the same road in both directions previously, and also seen the CEL light under similar conditions on various roads, so I don't believe it is that.

Confused
27-02-2017, 08:28 PM
The knock starts as soon as it moves into the 9.xxx range of AFR Map, and the timing goes from 20ish to 5

I think it's this change in AFR Map and sudden change in timing that's causing the knock with that much fuel.

I think AFR of 10 is too rich, you'll get best power at around 11-11.5 - that's certainly what we were aiming for when setting up my Anglia, and it's been pulling lovely without a tough of knock.

Davezj
27-02-2017, 10:30 PM
hi Piers,
personally it looks like you have gone to far to soon, you have made to many adjustments on this map and lost your way a bit. i would suggest saving the rom, but go back to the original map you started with and see if the knock goes away in the areas you are looking at.
then start again but make smaller and more considered changes to the map.
keep in mind that after making adjustments on the cells you need to make adjustment s to you need to change all the cells around them to smooth the map out so the ecu make smooth changes to the timing and AFR when it adjusts itself when knock come in.

have you watched all the videos in the this thread it will give you a very good idea about what to do and what not to do when tuning a map.

https://www.clubvr4.com/forum/showthread.php?67698-Basic-Introduction-to-ECUflash-rom-tuning-and-Evoscan-logging&highlight=basic+ecuflash

i had to watch them 5 or 6 times each to get a good idea on how to tune a map, it is not easy to get your head round and get things right, if it was everybody would be doing it.

Piers1989
28-02-2017, 02:40 AM
hi Piers,
personally it looks like you have gone to far to soon, you have made to many adjustments on this map and lost your way a bit. i would suggest saving the rom, but go back to the original map you started with and see if the knock goes away in the areas you are looking at.
then start again but make smaller and more considered changes to the map.
keep in mind that after making adjustments on the cells you need to make adjustment s to you need to change all the cells around them to smooth the map out so the ecu make smooth changes to the timing and AFR when it adjusts itself when knock come in.

have you watched all the videos in the this thread it will give you a very good idea about what to do and what not to do when tuning a map.

https://www.clubvr4.com/forum/showthread.php?67698-Basic-Introduction-to-ECUflash-rom-tuning-and-Evoscan-logging&highlight=basic+ecuflash

i had to watch them 5 or 6 times each to get a good idea on how to tune a map, it is not easy to get your head round and get things right, if it was everybody would be doing it.

Thanks Dave, Garry,

Yeah I know I've kind of dived right in. Before I started I watched all the videos several times, and I've been reading up on all the relevant info I could find from Merlin's guide and other forums / videos / google.
It all started out relatively smoothly but I've been making it less and less smooth trying to cure this knock.

I didn't realise that adding more fuel and pulling timing could cause the knock if it was too sudden.

The way I got to this stage was pretty much flash ROM, increase wastegate duty cycle, increase load target and add fuel. Then I've been adding more and more fuel and pulling more and more timing.
I'm aware it's too much fuel which is why I wanted to ask what I'm doing wrong as I know its not at all optimal for power or longevity.

I'll go back to the baseline, do some logging and try and start from scratch making it all smoother and hopefully it will go away!

Also I need to look at connecting my AFR gauges output to the ECU so I can log the actual AFR

Piers1989
28-02-2017, 07:04 AM
Ok so I've been out for a couple of hours this morning.

Went back to stock and all seemed fine, didn't go too fast so no use of 5th gear under load.
Gradually made small changes and kept everything smoother around the cells I was adjusting.

I haven't dropped the AFR too much, It was hovering around 11.5 on my gauge, as I gradually increased things everything still seemed perfect in 3rd gear every time, and 4th gear all but very minor blips as I appreciate its running about as lean as I would like it too at this stage.

I've only made changes increasing the load target to 185 max and I'm now hitting around 0.8bar boost, but hitting 5th gear it still suddenly reads knock in significant amounts.
It seems off to me that this only blips in 4th gear (which I appreciate at this AFR it should probably be richened), but then in 5th as soon as I put my foot down after the upchange the CEL immediately comes on and I back off after half a second or so.
After every gearchange / foot down at medium RPMs, my load spikes high around 180, troughs, then continues flat at around 150-160. The knock isn't solely limited to the spike but this does trigger it in 5th for sure.

If I get a chance tomorrow I'm going to reflash the stock ROM again and focus on entering 5th gear and see if it still registers it there - I didn't spend any time testing this today and retrospectively I should have!

My drivetrain is currently very noisy for reference, gearbox rattles in idle and at certain RPMs and whines in 1st 4th and a bit in 5th. If I find it still reads knock when upchanging to 5th (on the stock ROM) is it likely to be the knock sensor not liking the frequency of gearbox vibration?
I intend to have the box refurbished but it's one of those big specialist jobs I haven't gotten around to.

Davezj
28-02-2017, 01:58 PM
You should not be getting any boost spikes this is bad for tuning. You should sort out you boost spiking first before you start tuning the fuel and ignition.
You should be able to tune the boost solenoid via the ECU to give you a quickish boost rise to say 14 psi and stay stable.
Personally I find the standard boost curve is set quite well to avoid boost spiking. The only thing you need to adjust at first to increase the boost is the added value from stock 40 to 80. His should give you about 1 bar of boost. If you need to go higher then you have a good base to go from.
You need to have the boost correct set before fuel and ignition timing because if you change the boost level you will have to retune the fuel and ignition.
I would set a boost level you are happy with primary concern is stability. Nice flat line or as close as you can get it once max boost is achieved.
Then tune for the boost level.
If you adjust the boost up for instance after you tune fuel and ignition then you will move high load pull of the engine up the load scale into an area where you probable have not adjusted these cells from factory default settings and that is not good. You probable be getting less power than you had before the boost was turned up.
You will have to back and tune these cells now.
So get the boost sorted before you tune fuel and ignition.

By the way have you got used to the interpolate function in ecuflash, this allows you to fill in the outer cells of a range and the software will add the inner cells for you in a smooth progression. You can use this in a single line of cells or over an array of cells.
It is a very useful tool to be able to use.

Sent from my MI 5s using Tapatalk

Piers1989
28-02-2017, 04:22 PM
You should not be getting any boost spikes this is bad for tuning. You should sort out you boost spiking first before you start tuning the fuel and ignition.
You should be able to tune the boost solenoid via the ECU to give you a quickish boost rise to say 14 psi and stay stable.
Personally I find the standard boost curve is set quite well to avoid boost spiking. The only thing you need to adjust at first to increase the boost is the added value from stock 40 to 80. His should give you about 1 bar of boost. If you need to go higher then you have a good base to go from.
You need to have the boost correct set before fuel and ignition timing because if you change the boost level you will have to retune the fuel and ignition.
I would set a boost level you are happy with primary concern is stability. Nice flat line or as close as you can get it once max boost is achieved.
Then tune for the boost level.
If you adjust the boost up for instance after you tune fuel and ignition then you will move high load pull of the engine up the load scale into an area where you probable have not adjusted these cells from factory default settings and that is not good. You probable be getting less power than you had before the boost was turned up.
You will have to back and tune these cells now.
So get the boost sorted before you tune fuel and ignition.

By the way have you got used to the interpolate function in ecuflash, this allows you to fill in the outer cells of a range and the software will add the inner cells for you in a smooth progression. You can use this in a single line of cells or over an array of cells.
It is a very useful tool to be able to use.

Sent from my MI 5s using Tapatalk

Hmm, Let me check the logs, I'm pretty sure it was spiking even on the stock ROM - its a new(last year) boost solenoid too.
I'll try it that way, just increasing the adder for now and see what the result is too.

What could cause the spiking?

Yes Dave I have been using the interpolate function a little bit to try and smooth things out when I was making changes, but this time round I've tried to make very small changes so did most of it by hand.

EDIT: Added a graph below, you can see the load spikes then settles, this trend follows the boost spiking.
This is with the stock ROM.
76754

Confused
28-02-2017, 04:45 PM
You've checked the obvious things like engine mounts are still solid - the engine isn't rocking and knocking against the chassis, the exhaust is fixed correctly and isn't knocking against the engine/chassis, and that there's nothing loose in the engine bay that was removed and not subsequently fixed back in place?

You can try adding WGDC, AFRMap, TimingAdv and Airflow to your graphs in future - this will help you see any sudden changes and give a bit more information.

If you can get the wideband output wired up to the ECU too before you mess around too much more, that would be really useful as well.

Piers1989
28-02-2017, 05:10 PM
You've checked the obvious things like engine mounts are still solid - the engine isn't rocking and knocking against the chassis, the exhaust is fixed correctly and isn't knocking against the engine/chassis, and that there's nothing loose in the engine bay that was removed and not subsequently fixed back in place?

You can try adding WGDC, AFRMap, TimingAdv and Airflow to your graphs in future - this will help you see any sudden changes and give a bit more information.

If you can get the wideband output wired up to the ECU too before you mess around too much more, that would be really useful as well.

Mechanically, I don't really have much experience or skills with anything. In terms of electrical and computer based stuff that's where my expertise lies. I'm looking to change this though, just bought a kit with a jack, axle stands, slide trolley thing - and we recently got a huge socket / driver toolset for work I can use.
I haven't had a garage specifically look at these things, but the car has been in and out for bits and bobs and nothing has been reported. It's going tomorrow for the coilovers and cambelt, so I'll request its checked over for anything like this.
There isn't anything obvious rattling around, other than the old autobox plugs. Speaking of which I still need to connect the reverse light....

I was thinking just the same with the wideband, do I just connect it to pin 75 on the ECU? I don't have the serial programing cable for my Innovate MTX-L but from the factory the second analogue output reads 0V at 7.35 AFR and 5V at 22.39 AFR - sounds suitable?

I normally do log AFRMAP, WGDC and Timing on my logs too, but to make the graph less cluttered I excluded it. I will add airflow next time too.
Here is the log with more stuff on it for the stock rom.
76755

Confused
28-02-2017, 05:26 PM
Yep, just hook up the wire to pin 75, and enable the WB02 field - you may need to tweak the formula to get the correct AFR showing :)

Piers1989
28-02-2017, 05:51 PM
Yep, just hook up the wire to pin 75, and enable the WB02 field - you may need to tweak the formula to get the correct AFR showing :)

I'll give it a go tonight if I get a chance - been up since around 1am and have to go and get supplies after work to make a more suitable temporary accommodation for my chickens as they've indefinitely extended the bird flu restrictions up here!
Depending on tiredness may have to wait till I get the car back from cambelt / coilovers.

galantnight
31-03-2018, 06:47 PM
I know this is from last year but what was the outcome of this ?