k5383

iTrader: (10)

Going to be a little long winded, but I'd like to explain my entire situation past/present.

Bought the trans from the junkyard (96 model), first installed with stock converter.

Utilized LQ4/4L80 flexplate, with the 1/4 or whatever size spacer, when I first fired the engine up the from pump seal leaked fairly badly.

Pulled trans and replaced seal (napa part if it matters) still leaked, so I spaced the converter back with some grade 8 3/8 washers.

Trans no longer leaked, shifted through gears properly. Drove it that way for 3/4 months, only issue was trans never locked.

Finally got around to purchasing/installing stall converter from FTI.

Used LS1/4L60 flexplate, still used the washers bc it just "looked" like it was being pulled out of the transmission too far.

Still no lockup.

Today: I re-checked my TCC relay, realized the polarity for the brake switch was reversed, swapped them, test drove the truck.

It attempted to lockup once, then didn't do it again.

Came home got my laptop/hp tuners, modified my tune, intial test drive lockup tables were 100% stock.

Locked out 3rd gear lockup, and modified TPS/MPH tables so it wont lock below 50.

Test drove again, still no lockup, tested lockup via commanding it on. converter locked, accelerated began to smell ATF. Limped the truck home, got out, saw the fluid leaking out slowly from the pump seal again.

Suggestions? It's dark now or I'd unbolt the converter from the flexplate and get actual measurements but for now here are some pictures.

k5383

iTrader: (10)

Heres the pics with the converter loose from the flexplate, pushed all the way into the trans.

I added a second washer and it stopped leaking, went for a test drive all is well except still no lockup.
\

01ssreda4

iTrader: (96)

Well did you try commanding it again? Is the computer commanding lockup?

WE TODD DID

iTrader: (2)

Is the o-ring on the input shaft?

k5383

iTrader: (10)

This is what I'm wondering about now, but I'd assume it wouldn't lock via the computer if it was missing and or messed up. Really don't feel like dropping the trans if I could rule that out via logic.

It still commands on VIA HP tuners.

01ssreda4

iTrader: (96)

I'm sorry, more clearly. Is the computer commanding lockup? If yes is it locking? Have you tried commanding lockup? If yes what was the outcome? Trying to get a clear picture of what's taking place.

k5383

iTrader: (10)

The tune is set for the converter to only lock in 4th gear above 50 mph.

Cruise at 60 (speed given via hp tuners gauge) I've also verified that the TPS % for this speed is below the threshold for when it should lock.
Example: 28.5% TPS lock above 50, the say at 60 my TPS is at 22.3, hopefully that makes sense

Converter doesn't lock via the tune, I know this because the trans builds heat extremely quickly, blipping the throttle results in a 3-500 rpm jump.

If I command "TCC PWM" via HP tuners it will lock, and drop around 5-600 RPM.

01ssreda4

iTrader: (96)

Sounds like the computer is not commanding lock. You've proven through the controls that you can force it to lock but something is keeping it from locking during normal operation. Misfires or false misfires will cause this problem.

k5383

iTrader: (10)

The misfire tables are maxed out, here's my current tune. I'm going to triple check the relay, and the pins at the trans for the hell of it again tomorrow.

I'm almost positive there isn't an internal trans or converter issue, nor the O-ring being a problem given the fact I can lock the trans via the laptop.

I'm at my wits end with this haha

01ssreda4

iTrader: (96)

I am not going to give you false info about misfire tables because I have not fooled with them that much. I will say the converter locking and unlocking is directly linked to the computer sensing misfires. i will also say aftermarket converters are notorious for giving false knock. My understanding is the misfire part of the tune is very delicate and simply changing the weight of the converter can make it go haywire as it was specifically engineered with the stock converter's weight in mind. By commanding lock, and getting it, you've proven there is no mechanical problem with the car. This sounds tune related only. I would suggest going more in-depth by posting in the PCM section or trying your hand at HPTuners forum. There are some super smart guys around that are willing to help if you are patient. Put it this way, the computer is capable of locking the converter but is choosing not to lock it for some specific reason.....now you must find out why its not deciding to do it on its own.

k5383

iTrader: (10)

Precisely, and that's honestly where I'm at currently. I've posted in the tuning section with this issue before and we still couldn't fix it.

Thanks for your input

kinglt-1

iTrader: (26)

If I remember correctly you need to turn off mis-fire detection and several codes in the pcm. The aftermarket stall causes the pcm to freak out and will not let the converter lock.

01ssreda4

iTrader: (96)

Check/Search around on HPTuners forum. Great in-depth info over there. If I was having your issues, and I may one day, that's the #1 place I'd look.

AJII

iTrader: (7)

Your medium RPM misfire table looks stock. Max that out and try again

k5383

iTrader: (10)

Wow.. No idea how I over looked that..

Changed, I'll re-flash first thing and report back!

k5383

iTrader: (10)

Maxed all the tables out in the misfire section, test drove, no lockup.

Checked relay wiring was as follows:
30- keyed 12V
85- ground
86- 12V from brakes depressed
87A- to PCM

I checked this against LT1swap's schematic and his is as follows:

30-to pcm
85- 12V from brakes
86 ground
87A- keyed 12V

I swapped 87A and 30 around on the side of the road, didn't change anything. Didn't bother to swap 85/86 because from my understanding so long as one has power and the other has ground the relay will function properly..

Relay has an audible click when the brakes are applied.

01ssreda4

iTrader: (96)

Relay looks correct if the pcm is looking for 12v+ when the pedal is resting and nothing when you're braking. For some reason that sounds backwards to me. Try swapping 87 (empty) and 87a.......Can you verify what the computer is looking for during braking? I know the brakes unlock the converter.

k5383

iTrader: (10)

Doubtful, it's in a swapped truck. I could be wrong, I'd be very impressed if it could somehow tell.

Fella on HP tuners board told me to change some stuff in my misfire tables, I've done that and it's stopped raining, I'll switch 87/87A and see what happens along with his suggestions.

Update: Still no lock, I drove 2 miles with wire in 87, 2 miles back in 87A. Nada

Second question... When it puked out fluid, I blocked the tires and left it in drive, checked the fluid it was just over a quart low. Added enough fluid to where it was in between the dots.

Today after a 5 mile test drive (trans hit 140 degrees) checked fluid again, it looks like it's overfilled by almost a quart.

I'm running -6 feed lines into a large aftermarket cooler up front, I anticipated that it drains back into the trans from the cooler when it's shut off. Which is why I've never checked the trans when it's been cold.

jeremyfrank14

iTrader: (19)

You try and disable P1860.

Still doesn't work try disable P0740 too.

Just a thought if your not using a pwm signal to lock it up.