'95 with 260,000 miles. Brute force hd aem air intake; #6 plate; single stack

Problem: take off very slow, runs good when it shifts into od (will smoke a little). If you try to put too much peddle to it at any point after 3 gear, it will down shift and not shift until you let up on the peddle a little. What do we need to do to adjust this right? Should we run the star all the way forward?? Any advise would be greatly appreciated.

 

Is it down-shifting, or is it the torque converter unlocking? The converter is supposed to unlock under WOT so that the engine spins more RPM. This allows the turbo to build boost quicker.
This works alright for a stock motor, but really brings the suck for a modded one. We have the fuel to get the turbo boosting pretty quick even with the converter locked.

You can install a switch to get around the problem.


Good luck,
Chad

 

Not sure, good point. Will check out better.

 

Start here> TPS Testing and Adjustment

 

I have a 94 that was acting pretty squirrely ... the only electric device on ym truck (it's an all mechanical 12V) is the tranny... specifically the TPS and speed sensor that tell the solenoids that control the OD and lock-up when to engage based on speed versus throttle position. I did a mod to my TPS sensor based on info from here that allows me to clean the sensor (drill a small hole in the back of it... squirt in some alcohol.. run it through a dozen times by hand... let it dry and then seal it with RTV) and also a wiring mod that is a work around for jumpy voltage outputs... I wired in a cap and a variable resistor that allows me to alter the output of the tps to where I want it... so now my tranny goes into OD and the coverter locks up at 45 mph and I'm getting 25 mpg on average... I wired a switch to disconnect the converter lock-up and have the factory switch to disable OD when I want... usually when I'm on the highway and want to pass I just hit the OD disc switch and it throws the truck into drive... I shoot up to 80 or so and re-engage the OD... Girls like it when you do that... Kind of like fake nitrous... they think it's cool. (laughing my *** off as I type this because it's SOOO true). All of this can be found if you do an advanced search... you just can't beat this website for fnding cheap fixes for your old 12v... when I had this problem the dealership wanted to throw a $1500 tranny at me... said it was the tranny... too many miles for it not to be... yada yada yada... for $5 worth of parts and a little elbow grease I havn't had any problems since xmas of '07. I really should look up the guy that came up with that mod and send him a card or something... LOL.
I hope this helped to put you in the right direction...

Johnny

 

Thanks...Great advise...Can try drilling the tps, but a little iffy on the resistor thing...not real good at all the electrical things.
Just to restate the problem we're seeing, the pickup shifts through all gears just fine unless you're really hammerin on it. In this case, it will run through 1st and 2nd and then make you let off for it to shift into 3rd and again into 4th. Sorry if I wasn't real clear on this earlier...we were driving it today and paying close attention to everything a little better.
If you are at cruising speed (and especially if you're pullin anything of substance) and you need to pass someone, when you put your foot in it, it feels like it is down shiftin and you have to let off before it will go back into 4th. It's extremely annoyin. After really payin attention to it today, I believe what we were construin as 'down shiftin' is actually the tc unlockin.
Does this sound about like yours, Johnny?

 

My tranny reacts this same way. About 7/8 throttle the T/C will unlock even with O.D. off. It is really annoying like you said especially when towing. I thought my new trans, TPS, T/C, and VB would fix this, but not so much. Also I don't know if this is your problem, but the tech that built and installed my new trans said that the truck seemed low on power. At that time the T/C would unlock at 3/4 throttle. Well after some research on this site, he was right. I had boost and fuel leaks as well as a few other small problems that really added up. I fixed those and it helped but didn't totally solve the problem. I am going to try the lockup switch next.

 

I'm puttin the switch in tomorrow. Maybe this will solve everything. Thanks for all the help and advise.

 

Put the switch in today. Made a world of difference. Many thanks for the advise. It runs like a new pickup.