TPS and Tranny cant get along under load!

[Pinger]

It is currently on the hole closest to the pivot on the TPS. I get the biggest range reading from there. I tried others and it won't produce as big of a range.

Suspect you are going to have to go the opposite way at the carb - slow it down relative to pedal so the TPS can keep up.

Everything is locked down and nothing is moving at idle but, like I said, the numbers on my meter bounce around at idle when the motor is on. Is that normal?

Can't help but think that is due to the cable being under constant tension (and flapping about) rather than there being a bit of slack. There should really be a stop for the TPS arm to rest again at idle position.

Also, I am concerned about the random low reading that pops occasionally. I have a new TPS coming on Tuesday - I will be able to compare the readings between the new one and this one then.

If the new one has a different response curve, maybe a solution right there. Keep us posted!

 

[Erik the Awful]

Your voltage should not be jumping around.

From the pic on the third page, it looks like if you can drop the bracket that holds the throttle cable half an inch, it might get a bit more range.

 

[ROBERT McCORMICK]

Need a good trans tune now. Hopefully more then just tps based unless you could use change of tps speed to downshift or some load access. They make a stand along controller for trans too map and tps based I believe perfect for carb if yours cant be tuned decent.

 

[TacosnBeer]

FINALLY GOT IT!

**********************************************

Okay, messed with it again today. Once I figured out how the mechanics of the brackets worked and what adjustments on the TPS and carb did to the numbers... I was able to get .64v at idle and 5.02v at WOT... it drives so much better now under load. The shift could be a bit harder for my liking but, it's smooth and solid and pulls well under load. It still does the sputter in OD but very little compared to before... its MUCH better than it was.

I was also able to get a more capable OBDII reader and found my truck had a C0237 Rear Speed Sensor Erratic code. So now I need to dig into that... No wonder my speedo is 10mph fast... supposedly the previous owner changed that before I picked it up?!? I know this sensor feeds the computer to run the tranny too so, this could be the final part of the tranny issue.

Through the new OBDII reader, I also found out I have no brake lights and reverse lights... LOL if its not one thing its another. I got the C0281 Stop Lamp Switch Circuit code... The turns, driving, and hazards work but brake and reverse don't. I need to buy stock in a parts store. I checked the connections and ground and they are all solid. Fuses are good too.

 

[MrPink]

it may be the rear lamp harness, they are shittyly made and a failure prone part.

 

[TacosnBeer]

it may be the rear lamp harness, they are shittyly made and a failure prone part.

If it was the harness, the turn, hazards, and driving lights would be giving me problems too. Since they work, the ground is good and there are no frayed wires. I am gonna check the brake switch under the dash today and the reverse sensor is on the tranny by the speed sensor so, will check that too.

 

[PlayingWithTBI]

I am gonna check the brake switch under the dash today

A faulty brake switch could cause your TCC locking and unlocking too.

 

[TacosnBeer]

A faulty brake switch could cause your TCC locking and unlocking too.

I unplugged and replugged the switch and brake lights are working fine now. We will see how long it lasts. I didn't realize that would affect the TCC... Hmmm well, the truck had brake lights before and I had the same issues with the tranny so... either its intermittent or not the issue. We will see. Adjusting the TPS helped A LOT. My speedo is off and bounced around with the fuel gauge too and it popped erratic VSS code so, changing that next.

 

[Pinger]

FINALLY GOT IT!

**********************************************

Okay, messed with it again today. Once I figured out how the mechanics of the brackets workedand what adjustments on the TPS and carb did to the numbers... I was able to get .64v at idle and 5.02v at WOT... it drives so much better now under load. The shift could be a bit harder for my liking but, it's smooth and solid and pulls well under load. It still does the sputter in OD but very little compared to before... its MUCH better than it was..

Really pleased to see you got on top of it. Understanding the nature of what you're working with helps massively.

I was also able to get a more capable OBDII reader and found my truck had a C0237 Rear Speed Sensor Erratic code.So now I need to dig into that... No wonder my speedo is 10mph fast... supposedly the previous owner changed that before I picked it up?!? I know this sensor feeds the computer to run the tranny too so, this could be the final part of the tranny issue.
.

I unplugged and replugged the switch and brake lights are working fine now. We will see how long it lasts. I didn't realize that would affect the TCC... Hmmm well, the truck had brake lights before and I had the same issues with the tranny so... either its intermittent or not the issue. We will see. Adjusting the TPS helped A LOT. My speedo is off and bounced around with the fuel gauge too and it popped erratic VSS code so, changing that next.

The speed sensor was a suspect early on and there was always the suspicion you had more than one thing going on. As ever, it's just a case of working through the list. TPS was the biggest problem though - now solved.

 

[TacosnBeer]

Really pleased to see you got on top of it. Understanding the nature of what you're working with helps massively.





The speed sensor was a suspect early on and there was always the suspicion you had more than one thing going on. As ever, it's just a case of working through the list. TPS was the biggest problem though - now solved.

I changed the VSS with p/n: STD SC130 which turns out was the exact same one that was in it. I had to bend the bracket that came with it to make it fit which makes me wonder if it was the right on the PO put in it... This is the one that all the parts sites said was a direct fit so...
I guess we will see when I drive it. My speedo was off by 10mph the entire time I have had the truck... hopefully this completes the issue and I can move on. Will know more today when I get it out of the garage.