Guys... No need to drill anything. The TPS from my 87 was adjustable and uses the same voltages. I just installed it in my 93. It fits. It works. It looks exactly the same, but with slots instead of metal lined holes.

Couldn't this mod be done simply by adding a spacing material on either side of the throttle shaft 'blade'? I guess it'* kind of hard to explain, but it would effectively do exactly what you are doing by adding adjustability, but without the risk of harming the sensor in any way.

I guess I'll just have to go out and give it a try tomorrow with my autotap in hand (if it'* not raining)... I've got plenty of things that I could pad the 'blade' with. If I get anything t work, I'll take some pics and let you all know. I just don't like caniballizing things when it may be easier to do it cleaner.

Yeah thats actually what I did. I took a zip tie, tied it as tight as possible around the arm on the sensor, then clipped all the excess off so its just a 'nub' on the arm. I can rotate it and add more or less 'advance' as I like. Probably not the best answer but it worked for the experiments.

That is more or less what I was planning on doing. Depending on the weather tomorrow, I may give this a try. My thoughts were to see what my values were in the first place then with the bolts out, move the TPS to the appropriate position for 0.7v idle and mark the difference. From there I'll know the exact amount of material to add either onto the throttle shaft or onto the TPS 'drum'. If it'* like all of the other TPS'* that I have had apart, it is just a little plastic cylinder with 2 little triangular protrusions that capture onto the 'blade' of the throttle shaft. Should be very easy to either super glue or just silicone on more material to these triangular protrusions and get the desired TPS values.

Ok, gave this a try today. My voltage via Autotap was sitting between 0.4v and 0.5v at idle and topped out between 3.9v and 4.0v at WOT. After the whole ordeal, it now sits at 0.7v at idle and 4.5v at WOT. And I must say that this is a night and day difference! I actually think that between the BCA and TPS adjustments, my TCC shudder is all but gone. I'll need to get some more seat time before I make that determination, but in all of the miles (~250 since the BCA adjustment), I never once felt the tranny shudder when going up a slight hill with light pedal pressure. Now that I have done the TPS adjustment, it feels even stronger with light throttle up hills!

The lower bolt on the TPS is pretty damn difficult to get to and leave it to me to have one that didn't thread out easily either (nothing alittle antiseize didn't cure on the way back in though). I ended up taking my safety T-20 bit and holding it with my needle nose vise grips and turning it 1/3 turn at a time. After removing the TPS, I simply took a very small zip tie and wrapped it around the pin in the throttle shaft. Then held the TPS in it'* relative position to verify that the voltage would not be too high. Came right in at bouncing between 0.6v and 0.7v. Once I finally got it all tightened back down it was steady on 0.7v.

Took me around 7 starts (start it up, drive alittle while, shut it down, start it up...etc) to get the idle to calm down, but all in all, this was well worth the effort.

I know this is an old thread, but it is linked from TechInfo so here goes:

HTH Do you Series I L67 guys get at your TPS screws?
I used extensions on a socket driver with a flat driver tip, a swiveling, ratcheting arm, a ratchet with screw driver bit in the socket, and I cannot seam to get the right angle to get any torque on those screws.
I disconnected all the wiring to the sensors on the front of the TB, removed the stove pipe for the EGR, and so far my endeavors have been fruitless.
I don't really want to, but do I need to take the water inlet to the T-stat off?

Remove the TB to do it, and replace the screws with hex pan head screws and star washers. Then get an L wrench of the right size, and grind down the short leg on it to make it into a shorty for adjusting.

Since this thread it up and at 'em again, I'll throw something in here.

When I did the TPS mod as indicated by the linked website, I noticed no difference in performance. I had to make very large changes in the size of the holes to make the necessary correction in voltage, but it seemed like it made no difference. This thread is full of people who claim a big change in how the car feels, but mine seems to be unaffected. Do I need a completely new TPS?

You need a more sensitive ***-dyno.

Seriously, according to the FSM, and the way the TPS works, this mod definitely has merit. There SHOULD be better throttle response.

But but but....... I AM sensitive



So is it a possibility I have a malfunctioning TPS? I know I made extensive voltage changes, but I can't feel 'em. The car still accelerates the same as it did, and still shifts exactly the same. My understanding is that these two areas should be affected by this mod.

In theory, what are the telltale signs of a TPS on the way out the door?