Torque converter shudder
 

Been trying to track down the cause of some knock retard...I've been through all the common causes, lean spikes, too much timing, cheap gas, etc. My thoughts now is it might be shudder from the converter. The KR only happens right before a shift. Sometime it only pulls .5°, sometimes over 4°. Anybody else experienced/fixed a problem like this?

Post a log or two.

Look at frames 1490 and 4870.

Hmm, thats interesing. Log torque converter slip to see what its doing. Are you locking the converter at high throttle like that?

Im gonna go out on a limb and maybe make an assumption like you've got pre-stages of whats up with my shit box 4L60. However I donno what exactly has caused my problems other than the Trans guy at the GM dealership up the way from my work says it needs a trans.

My old 91 had a torque converter shudder. Right before it would lock up the whole truck would shake. Almost like having a bent wheel or something. I put a additive from o'reilly's & it went away.

No, converter lockup at WOT is disabled. Weird thing is the TCC dropdown menu on the PIDs list doesn't come up on my netbook where I do my scans...but it comes up no problem on my main PC where I look at the files.

I'm gonna assume thats not the reason cause its a brand new transmission. Its only got maybe 700 miles on it since the complete teardown/rebuild, and 500 of them were very easy break in miles cause of the new gears in the rear end.

Delete the os file in the scanner folder, that will make it rescan for all possible parameters. Thats what HPT told me to do when the LTIT wasnt showing up.

Finally managed to get the TCC slip PID in there. Actually, I didn't do a thing, it just sort of showed up in my PID list... Anyway I made a log, and TCC slip is always at 80%, no matter what I'm doing. Idle, WOT, its all the same. So I am officially confused.

Log the rpm not the percent.