Knock Count
 

So I'm starting to see a lot of knock counts. I can't determine if it's ghost knock or real knock. I'm assuming it's real since it only detects knock counts at a very specific rpm range. At low load, around 3000-4000 rpm, it will start detecting knock counts. WOT and ranges before or after that area no knock counts. Any ideas what could be causing this? It didn't use to do it before. No changes have been made. All of a sudden seeing 50-100 knock counts within 30minute street driving.
I pulled the spark plugs and they all look similar with no signs of problems.
I was thinking maybe it was bad gas (e85), but even after a recent fill up no change.
I was also thinking it may be the cold weather, but regardless of how much fuel i add or take away, or timing i add or take away, the symptoms remain the same.
The only other problem I can think of that I haven't checked is that maybe the fuel injectors are getting clogged somehow? Fuel pressure remains the same at 45psi. Might pull the injectors to get them cleaned then add a fuel filter in-line.

If anybody has any other suggestions to check for lmk. Car drives fine just like before and doesn't make any weird sounds.

Doesn't sound like you are getting actual real knock to me based on what you said. Low load is usually not associated with detonation for starters. An engine will knock under heavy load if its prone to that for typical reasons.

Turn the knock sensor off, it is junk and sounds like it is only showing noise, not knock. They are notorious for this and thus not needed.

I've been around the houses with the afr
and to the moon and back with the timing
It is NOT knock I still get "knock" counts 3-4k rpm at light throttle too
Ensure you have a zero count at WOT

As I self tune with a Flashpro I take most of my info from Hondata. If you search hondata false or phantom knock you will see plenty from them like their quote below
. If you retard ignition and the knock level does not change, then it is mechanical noise from the engine. The cause can be almost anything - aftermarket parts, a loose bolt etc. The most common causes are from after market valve train parts, exhaust headers and engine mounts.

My tuner has been tuning for decades and is VERY well known. He doesn't use the knock sensor on the F2xc engines due to the issues that the OP is having. A competent tuner doesn't need a knock sensor. This is why you read the plugs after a hard pull.

Agreed

As someone who works for an internationally respected tuning shop that builds some of the craziest R35's on the planet, I am going to have to strongly disagree with this. Do you really think high end ECU manufacturers are integrating multiple knock frequency channels and individual cylinder knock control because it can't be accurately monitored electronically?

A relevant article on the matter here, again by a globally respected source...

https://www.hpacademy.com/technical-...ing-for-knock/

Reading the plugs after a pull does NOTHING to prevent potential damage occurring on the run itself. What happens if conditions change when compared to when he was tuning the car and it actually does knock? Just pull those plugs and hope she holds together? It's honestly pretty mind blowing that you are really suggesting just reading the plugs after a hard pull in 2019. Is your tuner faxing over new cal's too? Part of your tuner's job should be actually finding the knock frequency for your car so that the ECU can protect the engine before it's too late.

I have to agree in this tuning logic. Reading plugs tells you if you have already created damage so that's a terrible strategy. There has to be some accurate way of getting a reading. If the knock sensor is picking up phantom knock, either learn to identify that read through it or better yet get a sensor/set up that is more accurate.

How??? Can you give an example of a more accurate knock sensor? Or an alternate way to mount it? Or is this irrelevant information?

I honestly don't know know what is actually going on here. What's true? Knock does not occur at low load and only at wot so I shouldn't worry? Or should I be concerned with the knock counts being recorded at low load between 3000-4000rpm?

I've also read in previous threads that phantom/ghost knocks occur mainly over cyl 2 and 3 since the location of the knock sensor is in that vicinity. Which makes sense why all my knock counts are being recorded from cyl 2 and 3. What I don't get is the fact that I am getting knock counts now whereas I did not before. Maaaaaybe I just didnt notice them being recorded before...maybe.

So, should I be worried about this or no? And if yes, whats the solution?

No, but he doesn't seem to be worried about it. Then again it's not his car, and maybe I'm just being overly paranoid. But if there is a problem and somebody else on this forum experienced a similar situation and reached a solution that's what I want to know. I just ordered another wideband so I'll be able to check my afr's again (until they foul out again) more accurately to play around with fuel.

due to the colder weather, it did start to run lean at cold startup and I could hear what sounded like misfires or popcorn popping warming up, but as soon as it warmed up it would be back to normal. My tuner said he could richen it but then it would idle really rich when warmed up. I'll play around with coolant temp fuel tables when my wideband comes in.

Get a bosch knock sensor and tune the frequency in the EMS by inducing knock on purpose. That sensor is much more reliable and what we use on sleeved motors as the stock sensor becomes useless at that point

This wasn't directed at you, it was directed at the guy failing to acknowledge technology may be better than JUST LOOKIN AT IT.

Charper732 answered your question about the RIGHT solution. I mean you could ignore these and keep driving, but I wouldn't.

What I would do, aftermarket sensor or not, is to rule out what's a real knock and what isn't. You need to induce knock at low RPM & low load while listening with audio equipment. Get those headphones on, start a logging, get into 2k rpm, low load cell on the dyno, make sure to select neighboring cells too as ECU can pull from multiple data points. Now slowly start advance timing in the selected cells until it starts pinging, STOP. You've successfully collected frequency information from the log and you know it's real since you heard it.

You now know what's a true knock and it's frequency. Fiddle with knock sensitivity tables and knock retard.

Alright, I think I found the reason to my problem. Something is wrong with my fuel setup somewhere. I just installed a new AF sensor and its running lean. Actually fluctuating. Even at idle, it would go from around 14afr up to 18afr then back down to 14afr then back and forth. At cold start up the AFR was all over the place, bouncing from 10.5afr up to 20afr then back down again. Once warmed up, it was initially idling around 16-20afr. I added some fuel to the low fuel tables and got it down to 14-18afr. But it keeps fluctuating and wont hold steady at an ideal 14.5afr. I have a hunch one of my fuel injectors may be clogged or not functioning correctly. Any suggestions on what may be wrong?

This is probably why my car was knocking, it was probably running lean at low loads.

if its a fuel issue related to one cylinder aka bad fuel injector, you should be able to get some confirming signs from the spark plug. Assuming your tuner set up your ecu to run closed loop 02 feedback (like stock) the afr should sweep, but not to the degree you are seeing. Typically 14.2ish to 15.5 is oem range. In your case it could be as simple as a vac leak somewhere, or something else such as a bad injector or something in the tune parameters. Pull the spark plugs and if you are not savvy at reading them, send us a pic of each one with making sure you document which goes to which cylinder.

i checked a few days ago seemed normal to me. Ill pull them again to get your guys opinion. Where are some common areas of vac leaks i should start checking??

Well considering the manifold is the vac generator simply speaking, id use this as your starting point, locating and tracing each point to its source, making sure you don't have a breach somewhere either from a bad hose, broken T fitting or detached from a component like a fpr or bov, boot gauge etc.

4
https://cimg7.ibsrv.net/gimg/www.s2k...a9d72cfcf2.jpg
3
https://cimg0.ibsrv.net/gimg/www.s2k...797196ad75.jpg
2
https://cimg5.ibsrv.net/gimg/www.s2k...ae92070b32.jpg
1
https://cimg3.ibsrv.net/gimg/www.s2k...d56e4ac694.jpg

How do they look? Cyl4 looks a tad rich. Also it was just coldstarted and idled for 5mins or so.

Actually #4 looks ok/fine, slightly damp but not rich running or overly lean, likely just incomplete firing from cold start/when you pulled the plug, its the least of what should be focused on based on how the other 3 plugs look which do look lean, based on white crusty color and also show signs of detonation as you suspected - which is the "popcorn" looking white dots/balls on electrode. Id say unlikely its a injector specific issue based on multiple plugs showing signs. Its not severe detonation, but signs are there so id say safe to move to next step of figuring out why/where the fault lies. Your tuner should be able to figure this out if he is worth two shits.

yea its primarily cyl2. Then 3. Hardly any in 1 and none in 4. Ill have to take apart my vacuum block and make sure its clean inside.

That would be consistent with my plug reading.

When was the last time you had a valve check/adjustment? Too tight of valves can cause some erratic running behavior and an increase in combustion temps which can lead to detonation in individual cylinders. Its something to keep in mind during your troubleshooting list. If you have individual cylinder tuning perimeters in your ecu, I would look there as well.

How exactly do you think knock was checked back in the day? It's not like we have been using knock sensors and advanced ecu's since the beginning and I wasn't talking about not using knock sensors that are accurate. I was talking about the junk knock sensor that is on the F2x engine. It is damn near impossible to get an accurate knock frequency with the stock knock sensor, so you may as well just shut it off until you get a better one and just read your plugs to confirm things. The issues with the stock knock sensor are the random phantom knock counts that happen that end up having the ECU pull timing when it isn't necessary.

My tuner doesn't tune on the ragged edge and we always pull the plugs to check for detonation signs after the final pull on the dyno. We don't rely on the stock knock sensor at this time to tell us if there is an issue. If I had a good accurate knock sensor on the car, then we will use it, along with checking the plugs.

https://youtu.be/giqibS76Fz4

keeps fluctuating at idle going lean then making popping sounds then goes back to normal to do it all over again

i got my valves readjusted last week. If anything its gotten worse. Im thinking its something mechanical. I just got my injectors cleaned today (altho initial flow test looked fine) and threw in new ngk 8 plugs gapped to the same .017 and no improvement.
the only thing left in the fuel system is the pump and regulator...

Dude maybe its just the flashpro. Its running totally fine now. No more leaning out. No more knocks. Im losing my mind over this. Im done. Just taking it back to me tuner and throwing it on the dyno. Donno why its running fine all of a sudden...

Sorry my thread seems like im rambling all over the place. But my car is behaving as such. So once fully warmed up (not just coolant temp warmed up, but oil temps warmed up) it exhibits all those symptoms much less. When the oil is still cold, the afr's will fluctuate, record many knock counts (like 5-10 knock counts every time i pass 3000-4000rpm). I wonder if this is mechanical or software. Thing is i dont think there are parameters in flashpro to fix this problem via tuning. Now, with the cleaned injectors and new spark plugs it still picks up knock counts in 3000-4000rpm range but only in 1st and 2nd gear and now maybe only records 1 knock count every other run past that rpm range. I have a feeling this will progressively get worse again. I really want to get to the root of the problem. For whatever reason replacing the spark plugs reduced the symptoms. Once warmed up, AFRs are good too at cruising and idle. Ill check again tomorrow morning when its cold to see if the knocks and lean out are worse than they were tonight.

Just a guess, but could it possibly be due to something with your coolant temp sensor settings? Have the warm up enrichment table and things been set up properly?

Probably a long shot but what about the coils? If you have a lot of miles on them they could be getting weaker.

Could be the coils, could be anything lol.. Car has 70k miles. I dont think the coolant temp fuel tables were setup. But it seems irrelevant to my problem since it was knocking even after it was fully warmed up.
Thing is my car was running 100% without any issues before. All of a sudden about a month ago it started to lean out on cold starts and started knocking even after the car was fully warmed up.
My afr's are within normal range but still recording knock in the 3-4k rpm range only at low load.
So far Ive:
1. Replaced spark plugs
2. Cleaned fuel injectors

There is improvement but problem is still there.

Yea I'll update the thread.
Here's a screenshot of my low fuel map
https://cimg7.ibsrv.net/gimg/www.s2k...098377f36d.png

And here's a screenshot of the water temp fuel compensation tables.
https://cimg9.ibsrv.net/gimg/www.s2k...2e66369176.png
Earlier today I was datalogging and making changes to my low fuel and ignition maps which seemed to help. At cold startup, it started to track back and forth again from lean to rich. Under 170deg in the water temp low fuel tables it used to be 0. I slowly increased it to 40.8% with gradual improvement to the afr fluctuation. The afr at idle stabilized to around13.8-14.5afr, but at this point the temp was already up close to 179deg. I'm beginning to think a hondata update or something corrupted my tune. I asked my tuner to email me my original tune and he says he no longer has it due to getting a new laptop.
On drives, I also realized most of my knocks were coming from 1st gear, seldomly from 2nd, and none from 3rd gear on. Studying the datalog, k control was in the 150's% in 2nd through 4th gear light throttle pulls with IGN at 0-4deg. 1st gear told a different story...with k control starting at 120% and gradually increasing to 133% allowing IGN to start at 10deg at 2400rpm then gradually reduce to 3deg by 4000rpm respectively. On this pull, 3 knock counts were recorded only in 1st gear. So it got me thinking, maybe its knocking in 1st because the timing is too advanced at 10deg. All the other gears the IGN is held at 0-4deg by a high k control and not knocking.
So I went into my IGN low tables and reduced the target IGN values in columns 4-9 and rpm values 2000-4000rpm significantly to see what would happen.
https://cimg8.ibsrv.net/gimg/www.s2k...5e57acafea.png
I know it's not smooth and pretty, but on my drive home I recorded zero knock counts. K control was around 80-90% in 1st and 2nd gears and IGN was 0-5deg in all gears. Now this could be a fluke since the car was fully warmed up by this time, but I'm curious to see if this made a difference. I'll check again this week to confirm any changes.

Also, what's everyone's IGN at around in low load acceleration? Like 20-30% throttle.

Your compensation numbers seem really high, but I'm no pro, so maybe someone else could chime in. I wonder if the closed loop is freaking out and fighting comp table to get you to 14.7 AFR or whatever it's targeting at a specific ECT.

Edit: I've learnt that you should NOT mess with ignition timing until your fuel table is complete and stable otherwise you just end up chasing your tail. So go conservative and basic on your timing to see if you can rid of knock and be safe, now get your fueling sorted out, then go back to tuning ignition.

K Control 100%+ tends to suggest that ECU is treating your tune as if you were on low (85) octane. I can see it pulling serious timing based on your K Control values.
Video about Honda's weird way of controlling knock too btw:


Here are FOUR base maps from Haltech and Hondata
https://cimg8.ibsrv.net/gimg/www.s2k...6d7200244d.jpg
https://cimg9.ibsrv.net/gimg/www.s2k...954b07b5bb.jpg
https://cimg1.ibsrv.net/gimg/www.s2k...1111c302b8.jpg
https://cimg2.ibsrv.net/gimg/www.s2k...8a0c8c321f.jpg


This is someone's custom SC 10PSI map:
https://cimg3.ibsrv.net/gimg/www.s2k...311f66f85e.jpg

did you get it figured out?