I've been reading for a couple of years now how the TPS should be adjusted to .99 volts at idle. I finally got around to measuring and adjusting it last weekend. I only wish I would have done this sooner!

After setting it to .99, a couple of driveability issues were improved. Throttle response was better. But the biggest improvement was how the torque converted behaved at highway speeds.

Before the adjustement, every time I let off the gas when going over 50mph and then getting back on the gas, the TC would always unlock and then a couple of seconds later lock back up.

Now it stays locked when I let on and off the gas.

I just elongated the screw holes and then got some allen bolts to replace the originals. 15 minute project.

 

how did you measure the voltage on the TPS and if you could. would you mind making a short step by step on the whole process??? thanks in advance

 

I am interested in this too. One of my customers has an "overactive" TCC on one of his trucks. Is the idea to have the computer "see" .99 volts? If so I am interested in the procedure as well. My observation in the past is that the voltage that the scan tool is not exactly (off by sometimes .2 volts). Using a DVOM would leave a few questions. Like what do you use for the com side, and do you look at the TPS voltage backprobed at the TPS or the computer.

 

staypuf & adaycj- this thread will give you all the details you need. Even though this is a Lightning thread w/ different style TB's, everything applies to the 4.6 & 5.4 NA engines.

The one area of disagreement I have with a post in that thread is where someone said to adjust the TPS with the Key On / Engine off. I adjusted and set mine while the engine was running b/c that is the voltage that really matters. While I didn't check this, I'm pretty sure the TPS would read a different voltage with the engine on vs. off.

One other thing I'd mention, some of the TPS that Ford put on their vehicles will make it more difficult to adjust. The original TPS on my truck had brass or metal inserts where the two screws bolt onto the TB. I happened to have a couple of Ford TBs in my garage and I found one where the TPS was all plastic, so it was easy to open up the holes to move the TPS around.

TPS adjustment thread

 

Check out this post from the Lightning Forum:

https://www.f150online.com/forums/sh...ghlight=TPS%2A

Hope it helps.

 

Got it bookmarked! Thanks! Its an awesome thread...

 

Is there any reason to do this on an 01 4.6L with stock TB and TPS that seems to be running fine? Are they not set this specific at the factory? If I were at say, .975v, would I see any performance increase if I had set it to .99? Thanks.

 

Jackal - if you have a digital voltmeter handy, it doesn't take that long to see what it is set at. I don't think you can rely on them being set all the same from the factory.

While my truck is 3 years older than yours, my TB and TPS were stock/original and it wasn't set-up properly.