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Discussion Starter #1 (Edited)
I didn’t log anything until I had driven 1600 miles. The car has the stock tune.
The OAR was 0 even though it was always filled with Shell 93 octane.
I drove the car until it was below ¼ tank and filled up at another station. The OAR then went to -0.26.

At ½ tank I added 2.5 gal of Sunoco 100 octane, which if the remaining fuel was 91 Octane, then it should now be 93.25 octane.
I drove until the car registered empty and the OAR was still at -0.26.

I added 4 gal of Sunoco 100 octane and left to go to another Shell station on the interstate. Within 3 miles the OAR moved up to -0.33.
I filled the rest of the way up with Shell 93 so now my octane should be 94.2.
Since the fill-up I have driven 175 miles (now at 2400 total) and the OAR has remained at -0.33.

The knock control spark adjustment varies from 0 to -2.
No DTC error codes.

The other strange thing is that cylinder 2 always shows a knock of 1 even before the car is started. The other cylinders always show a count of 0.

So, does anyone have any ideas?

2020-09-11_Log_22lb.jpg
 

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Discussion Starter #2
So it appears that the Cylinder Knock/Combustion Performance Counter doesn’t work like I thought it did.

This is what ForScan says:
”Cylinder Knock/Combustion Performance Counter.
Counter for the cumulative number of ignition events with abnormal knock/combustion detected. This typically resets when the DTC’s are reset by the service tool.”

So that would mean there was one ignition event with abnormal knock/combustion that occurred and was recorded several months ago. I don’t think that is affecting the OAR/KOM number.

I used the ForScan clear DTC but the counter number still remains. Looks like it may take a service tool to get rid of it. Any way I think I will leave that off my data logs.

When I hit empty, I will fill it with 100 octane and see what happens.
 

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Discussion Starter #4 (Edited)
I tried that earlier today. I disconnected the battery neg and pos for an hour and then connected the neg and pos for 15 minutes. I hope that was enough to reset the KAM. It did erase the MyMode drive mode. Didn't have a chance to drive it after that but the OAR is still -.33.
Thanks
 

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I tried that earlier today. I disconnected the battery neg and pos for an hour and then connected the neg and pos for 15 minutes. I hope that was enough to reset the KAM. It did erase the MyMode drive mode. Didn't have a chance to drive it after that but the OAR is still -.33.
Thanks
When the OAR is reset, it should go to zero. What are you using to datalog? A Cobb AP? If so, I believe they have an 'OAR reset' function on them. If not, I would download forscan and run the OAR reset on that. Do not be satisfied until it resets to zero. Make sure you have your tank filled to the brim with 93 gas (I think ANY 93 gas is okay, but I personally have not used Shell, so I can't attest if that's your problem or not), and log a good few hundred miles on it. That should hopefully fix your problem.

The other strange thing is that cylinder 2 always shows a knock of 1 even before the car is started. The other cylinders always show a count of 0.
Its literally impossible for the knock count to start at 1 even before the car is started. My supposition is this is already registered AFTER you hook up your tool (or whatever you are using to datalog). If you can CONFIRM that the knock count is NOT resetting to zero after you turn the car off, as it should, then I would take it to the dealer and let them know. There might be something wrong with your sensors or the ECU itself.

Hope that helps.
 

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Discussion Starter #7
I am using OBD Fusion and ForScan.
So I let the car sit overnight with the battery disconnected and the OAR still didn't reset.
I never noticed that ForScan could reset the OAR. I must be blind, how do you do that?

I know it is impossible to have a actual knock count before it starts that is why I said it is strange.
So it appears that the Cylinder Knock/Combustion Performance Counter doesn’t work like I thought it did.
This is what ForScan says:
”Cylinder Knock/Combustion Performance Counter.
Counter for the cumulative number of ignition events with abnormal knock/combustion detected. This typically resets when the DTC’s are reset by the service tool.”
So that would mean there was one ignition event with abnormal knock/combustion that occurred and was recorded several months ago. I don’t think that is affecting the OAR/KOM number.
 
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I am using OBD Fusion and ForScan.
Cool. I use OBDFusion for datalogging also. I believe the Forscan OAR reset is ONLY on the Windows version, not on the mobile. Have you tried that? I'm 99% I could've sworn I saw it the last time I was in there. Alas, I'd have to go and apply for a new Forscan advanced license and all that, in order to fire it up again.

I think you might be misinterpreting the Forscan definition of knock. It definitely could've been written better, though. Yes; it will "typically" (and by "typically", I think they mean all the time) reset after a DTC clearing. But I'm fairly sure it will also reset after an ignition cycle. Again, I haven't really checked in with my knock counts in some time (I only monitor them, and don't log them), but I am also about 99% sure that they reset to zero after every ignition cycle. But you've given me enough doubt that I will check my monitor on my next drive to see what it says (if if is that I do happen to register a knock, which I haven't seen one in a while).

I always point ecoboost owners to this article by Stratified Auto that is an excellent read for 'knock knowledge':
Blog : Understanding knock and ignition corrections in your Ecoboost powered Ford : Stratified Automotive Controls
 

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Discussion Starter #9
I do use the Windows version with the advanced license. I will look again to see if I can reset the OAR.
I am not sure what to think, at first I thought the knock counter was suppose to reset when the car was turned off and then I read what ForScan said. I believe I might have been correct in the first place. I am beginning to think the ECU may be screwed up. Could be a problem getting the dealer to do something when there are no error codes.
I have a feeling that the KAM has not actually reset since the OAR stayed the same. Do you know of another way to reset KAM besides disconnecting the battery overnight and grounding the positive cable for an hour? I know the Cobb tool has that function but I don't want to installed a tune.
I have read everything from Stratified and thought they did a very good job. If you notice Google running slow it's probably because I wore it out doing searches.
Thanks for the replies.
 

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I am not sure what to think, at first I thought the knock counter was suppose to reset when the car was turned off and then I read what ForScan said. I believe I might have been correct in the first place.
You definitely got my attention to pay mind to it. I don't always hook it up, but I will until I can either confirm or negate what I said.

I am beginning to think the ECU may be screwed up. Could be a problem getting the dealer to do something when there are no error codes.
I mean, you can go in there and basically tell them that the OAR reset is not working. I think you're armed with enough info to be forceful about having them take a look at it, if you want to.

Do you know of another way to reset KAM besides disconnecting the battery overnight and grounding the positive cable for an hour?
That's basically how Ford Tech 'Make You Loco" tells you how to do it. So it should work. I just sent away for another advanced license, so I'll probably get it in a day or two. I'm also curious to double check my memory on what I saw. Let me know if you see anything that you might have missed.


I have read everything from Stratified and thought they did a very good job. If you notice Google running slow it's probably because I wore it out doing searches.
You basically have my attention because it does seem like you covered your bases before you came asking questions here, which not everybody does. You will figure it out.

Thanks for the replies.
You're welcome. (y)
 

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Nevermind. I don't have to wait for the extended license. It's basically copy and paste.:sneaky:

Did not see what I thought I had seen, and now I'm thinking I might have seen it on my procal software only (I have the FP tune) and not Forscan.

I thought maybe this might be it
37563


But according to this thread on the forums, the OAR stayed the same for his Ford Focus. I'd try posting my own thread? I've done so for other issues and have gotten back some decent responses. You would think that this is an easy reset of some stored register somewhere. Yeeeeesh.

Ford Focus MK3 "reset all adaptation" function - Page 4 - FORScan forum
 

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Discussion Starter #12
Thanks for looking at it. Looks like I'll hang out with Mr. Google for a while.
In 100 miles I'll be at empty and the fill it with 100 octane. If that doesn't work I'll call the Ford dealer.
I will let you know what happens.
Man, it is hot down in Florida. I was in Melbourne Beach to see my brother a couple weeks ago, and I thought Coastal Georgia was hot!
 
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Stop using Shell gas. It has additives that cause small turbo engines to knock at high RPM.
I think you missed this. Tune+ specifically won't tune someone if they tell them they're using Shell gas.
 
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Discussion Starter #14
Yes, I did miss that. Still can't find that on their webpage, they must tell you after you purchase the tune.
I wasn't going to use Shell again anyway.
Thanks
 

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Hey just wanted to let you know that I've been hooking up my datalogger consistently on every drive, but still haven't registered a single knock. So I still can't confirm if an ignition cycle resets the counter. I'll keep trying, though.
 

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Discussion Starter #16
Thanks
I've got 50 miles till empty before I fill part way with 100. I also purchased a scanner that can reset the KAM. It has become a challenge.
 

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Discussion Starter #17 (Edited)
Update:
I reset the KAM using an Autophix 7150 scanner. This set the OAR to 0 and set the cylinder 2 knock counter to 0.
In addition to the 100 octane I filled up with Chevron 93 octane. The mix should now be 94.6 octane.
Have only driven 32 miles and no change yet. Hopefully the OAR will soon be heading to -1.

Note:
The method of disconnecting the battery over night and connecting the positive and negative cables together does not reset the KAM on my 2020 HPP.

*Update:
73 miles since KAM reset. OAR = -44
 
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Discussion Starter #18 (Edited)
Success the OAR is now -1

The OAR reached -1, or if using KOM 1, at 83 miles after a KAM reset.
I used a mix of Chevron 93 and Sunoco 100 for an octane of 94.6.

**It took a KAM reset, using a scanner, to get the OAR to -1. It is possible the fuel was bad but previously even after 210 miles using a different station and 100 octane added the OAR would not move off -.3.

The method of disconnecting the battery over night and connecting the positive and negative cables together does not reset the KAM on my 2020 HPP.

From what I read Ford started using KOM instead of OAR with the 2018 models. They represent the same parameter but are the inverse of each other.
OAR is Octane Adjusted Ratio. The best result is -1.
KOM is Knock Octane Modifier. The best result is 1.

The equation for KOM is (abs(Signed(A)*256)+B)/16384

KAM is Keep Alive Memory
 
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Success the OAR is now -1

The OAR reached -1, or if using KOM 1, at 83 miles after the KAM reset.
I used a mix of Chevron 93 and Sunoco for an octane of 94.6.

**It took a KAM reset to get the OAR to -1. It is possible the fuel was bad but previously even after 210 miles using a different station and 100 octane added the OAR would not move off -.3.

The method of disconnecting the battery over night and connecting the positive and negative cables together does not reset the KAM on my 2020 HPP.

From what I read Ford started using KOM instead of OAR with the 2018 models. They represent the same parameter but are the inverse of each other.
OAR is Octane Adjusted Ratio. The best result is -1.
KOM is Knock Octane Modifier. The best result is 1.

The equation for KOM is (abs(Signed(A)*256)+B)/16384

KAM is Keep Alive Memory
Glad to hear it!
 
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