vdrumright Posted February 10, 2005 Report Share Posted February 10, 2005 Maybe this has been covered before but I'll ask anyway. I am experiencing KR when shifting into passing gear @ 3,200 - 4,000 RMP. Anyone else experience this & what did you do to correct it? My WOT runs have very little KR. Vince Quote Link to comment Share on other sites More sharing options...
SSminneapolis Posted February 10, 2005 Report Share Posted February 10, 2005 yeah vince..i have had that same problem...weird. wish i could help you fix it...good luck! Quote Link to comment Share on other sites More sharing options...
deezel Posted February 11, 2005 Report Share Posted February 11, 2005 Its difficult to get rid of the KR on downshifts. I haven't been able to trace it to a specific table, per se. There is some suspicion that a lean spot in the VE table could cause this. Quote Link to comment Share on other sites More sharing options...
SSminneapolis Posted February 11, 2005 Report Share Posted February 11, 2005 what has worked for me...and on other 03 truck (SS and non SS) that i hate tuned up...is the TCC apply release settings. it worked like a charm on mine and many others. i tried timing, VE and a couple of other things..and nothing really worked. i suspect that something else is going on with vinces truck... Quote Link to comment Share on other sites More sharing options...
BenKey Posted February 11, 2005 Report Share Posted February 11, 2005 Is this a transition from cruise to WOT? I get it. It can be tuned out, just need to keep trying on it. Erik may have a good approach for it. Quote Link to comment Share on other sites More sharing options...
TurbochargedBerserker Posted February 12, 2005 Report Share Posted February 12, 2005 There are two very similar problems that look like this, one is fixed by the TCC settings Ryan mentioned or by changing the shift points a bit, the second is more involved and actually is a transient throttle condition as Ben mentioned. The way I diagnose which problem exists is by manually down shifting into third. For some reason I can't fathom yet, manually shifting does not seem to cause knock in the first case, but in the second case, you'll still get knock. I messed and messed with my tune trying to fix the transient thing. It was completely fixed only by doing an SD tune to get the VE locked in. I also think that the IFR method of tuning LTFTs exacerbates the transient throttle problem because the VE table gets so far out of whack. Quote Link to comment Share on other sites More sharing options...
deezel Posted February 12, 2005 Report Share Posted February 12, 2005 Yes, the TCC settings help with the cruise to WOT kickdown KR on a relatively stock setup. I figured that Vince is probably having the other, VE-related, problem with his FI setup. Massaging the VE table or doing the SD tuning procedure would likely help. The "lean spots" in the VE table show up during transients because the airflow calculation is estimated from VE until the MAF can catch up. The lean spot is not necessarily in the cell where the KR occurs. It can be in the lower-RPM cruise cells that were in effect before the throttle transition. Quote Link to comment Share on other sites More sharing options...
vdrumright Posted February 12, 2005 Author Report Share Posted February 12, 2005 Thanks for everyone's imput on this issue. Unfortunately, my tuning has been put on hold for a while. The person that was generously letting me use their HP cable needed it back. I had it way longer than he anticipated and a big thanks goes out to him for his patience. I'll continue tuning after I sell some more fan harnesses..lol. So you guys that are considering the 05 fan upgrade let's get er done.... Quote Link to comment Share on other sites More sharing options...
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