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So I have been running my stock tune for the last week or so while I was testing out those changes to the transmission tuning I posted about. Today I was driving my son to school, which is almost entirely flat 55mph road, and was monitoring with my X4. I noticed my OAR was at +.96 and that my KR was deep positives, just like everyone is describing. I was watching on the way home and it was hovering in the +5/+6 range between 0.4 and 0.8 load.

The weird thing was, while driving along on this extremely flat road while the cruise was set to 55mph, all of a sudden it would just flip a switch and be pegged at -4 KR for a little bit. Like PEGGED there.

I rarely run the stock tune, never mind monitor it, but this was a fairly fresh tank of Chevron 91.

I bet this is why Gearhead has the KR set to come on at 0.8 load. I may change my tune so that the OAR only responds above 0.8 but leave the KR active.
 

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The "best fix" so far I have found for part-throttle knock, is to switch to E30 (if possible).

I recently found an E85 station close to where my father lives (and I visit fairly regularly). I chatted with the manager of the station, and they have no problems me filling up a dozen jerry cans.

Burning E30, I saw little or no part-throttle knock. In fact, most of the KR in part-throttle is negative now. But, after reviewing my datalogs with my tuner and fellow senior member, I found my HPFP just can't keep up to the demands of my truck with E30. The scariest part was right at the 2-3 upshift, and once in 3rd the rpms are too slow for the HPFP to keep up, so now I am looking at a HPFP upgrade.

Luckily, I am no longer married, so I don't have anyone watching how I spend my/our money anymore.
 

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There are, then, undoubtedly differing issues going on here that just reveal themselves in the same manner. By simply going to a higher octane or going to e30 or e50 I saw no change. Had to jump through hoops to tame it either way.

Sent from my Moto Z3 Play using Tapatalk
 

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Has anyone checked off the list that it could be the torque converter emitting the right frequency when locked?

I’ve had in the past where it has caused some sporadic false KR part throttle and wot.
 

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There are, then, undoubtedly differing issues going on here that just reveal themselves in the same manner. By simply going to a higher octane or going to e30 or e50 I saw no change. Had to jump through hoops to tame it either way.

Sent from my Moto Z3 Play using Tapatalk
Agreed. If you are running E30 (or higher) and still seeing +KR, there is definitely something not right that is causing a false knock. Especially if you still saw it on a stock tune and getting nothing but +.96 OAR.

Most people (if everything is operating correctly on the truck) and they suspect their fuel in their location, just make an E30 blend and see if the KR & OAR become more favorable.

And if E85 is not readily available, go to a hardware store and buy some pure methanol (gallon jugs are cheapest) and make a M25-30 blend. That will do the same as E30.
 

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Discussion Starter #66
Has anyone checked off the list that it could be the torque converter emitting the right frequency when locked?

I’ve had in the past where it has caused some sporadic false KR part throttle and wot.
Damn, I mean I guess that could do it, is there a way to check for sure?
 

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I have a stock tune setup to only adjust OAR at >0.8 load. It seems to have worked because my OAR is now consistently sitting around -0.67 vs positives or very low negatives a week or two ago.

KR still functions at >.4 like stock and havent noticed it running deeper in the positives than it was.
 

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Discussion Starter #68
Just took the truck out of hibernation today, Issue is still present.. of course.

However, I remembered something. the issue gets instantly worse if I go to use manual mode, if I select a gear at all OAR is guarenteed to go up to atleast .50 instantly and then continue to rise if I continue using manual mode. Does this info help at all in figuring out what could cause it? what is different in manual mode that would be triggering this?!
 

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Just be cautious with manual mode as a lot of people lug the truck which causes KR at part throttle.
 

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Discussion Starter #70
Just be cautious with manual mode as a lot of people lug the truck which causes KR at part throttle.
Nope no lugging here, downshifted a few times before getting on it and the second I downshift and give any throttle OAR goes way up. Assuming it came down from the last time the false knock made it rise
 

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Nope no lugging here, downshifted a few times before getting on it and the second I downshift and give any throttle OAR goes way up. Assuming it came down from the last time the false knock made it rise
I would ask your tuner to adjust your tune so that OAR is NOT adjusted when load is under 0.8. I am willing to bet your situation will improve dramatically.
 

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Discussion Starter #72
I would ask your tuner to adjust your tune so that OAR is NOT adjusted when load is under 0.8. I am willing to bet your situation will improve dramatically.
Sounds good I will see what Torrie and Matt say, I also just sent Boostking a message to see if I can get going on one of his tunes!!
 
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