4l60e no convertor lockup

Working on my 2003 s10 with a 2003 5.3L swap. im running a 2005 express van calibration to make everything work properly in the s10.

For the first month or two and couple thousand miles everything worked fine. Then one day i lost lockup on the highway. next day i got a cylinder 5 miss fire. found a plug wire that was too close to the header and assumed that would fix my issue. fixed the plug wire and still no lockup.

i thought i might be getting a random miss and maxed out the missfire tables. still no lockup.

Then i set the trans to lockup at low speed in second so i could log the problem in the neighborhood. I can see on the scanner that the brake switch is working properly, low tps is working. the TCC state switches from off to apply enable to locked. TCC PWM goes from 90ish to 100ish (thats what the tune is setup for). I can command 100% TCC PW and lock the convertor from the scanner and i get full lockup. But when i try and let the PCM command lockup it will never lock.

Im still running the stock s10 trans with 170k on it. I want to verify that its a mechanical issue like i think before i go digging into anything.

attached is my latest tune and log file. in the log file anytime the verter is locked is when i commanded it with the scanner controls. Attachment 47828Attachment 47829

Forgot to say. Besides the #5 missfire i have not gotten any codes

Missfires will prevent TCC lockup last I knew.

Per the first post i fixed the miss and even maxed the missfire tables out and still had the same issues.

Duh, I didn't notice this until now. Did you do a trans segment swap yet? I believe the Express software was programmed for 4L80E transmissions. This was at least the case with my 2002 Express file. I had to have support do a trans segment swap from 4L80E to 4L60E.

I had a 5.3 4l60e express tune. It worked for a month or two at first.

Hmmm, If the lockup stopped after the misfire, and you corrected the misfire, did you clear the code from the PCM? Is there any PENDING misfires? They don't trip a light.

Quote:

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Originally Posted by Mike1995

Hmmm, If the lockup stopped after the misfire, and you corrected the misfire, did you clear the code from the PCM? Is there any PENDING misfires? They don't trip a light.

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Im not 100% certain that the miss occurred the exact same time the lockup stopped. there were a couple days worth of driving where it was around town where it would not get to lockup speed.

With that being said i did check for codes and scanned for current and history missfires, i logged TCC missfire off in the status bits and it always said "no" meaing lockup is not off due to a missfire. I even had the battery out for a few hours while working on the AC lines. were cleared and checked again after the battery was installed again.

The part that really has me confused is that i can command it with the scanner no issues, but that it wont work under normal driving when it appears i have all the necessary signals in the necessary states (unless im missing something).

The trans feels fine, the 1-2 shift is sometimes a little harsh but not neck snapping like some of the vehicles i have worked on the have had the TCC solenoid bore wear issue.

Add the following status bits and go for a drive. Hopefully it will be obvious to whats disabling your tcc, but if not post up the log and your tune.

I had all but one in the log i posted earlier. only one i didnt have was TCC ramp exceded. As far as i can tell im getting everything i need to lock the convertor. however the TCC solenoid enabled never comes on. it only switches from off to on when i force lockup with the scanner.

in the log i posted the times that its is acutally locked is when im playing with the scanner.

here is a screen shot of the log. It shows that its locked and the PWM is 100% however the lock solenoid is not enabled.

The apply time is long, maybe i need to log that last bit and see whats going on.

here is another short log with that missing status bit added. same tune thats posted above

I have no idea. Everything looks to be correct.

Thats exactly what i though.

I suspected it was a mechanical issue, but i wamted to make sure there was not an electrical or tune issue first.

I appreciate all the help on this ao far. I will update this once i find the issue.

Talked to a buddy that rebuilds 4l60's on the side. he said to try changing my lockup tables to 100% and 100% or try commanding 90% lockup with the scanner.

He said he saw a few times where a 60e wouldnt lock on its own but would with a techII (tech II defaults to 100% PWM he said.)

He is thinking that 100% PWM is enough to slam the valve and make it work properly but going from less than 100 and ramping up isnt enough to "slam" the valve and get it to work. Just a theory, but its something to try.

tried the 100% PWM and no luck.

was working on a tune for a buddies camaro and noticed his P1870 code settings are WAY different than the truck/van ones. i might try throwing those lower slip values into my tune and see if it throws a code.