TPS Bypass Switch

[AugustDiesel]

I have to assume you are using the old (88) computer. The tps had only two functions when mated to the 700R4. Controlled the EGR (if installed) and commanded the lock up. Your shift patterns are controlled with a throttle valve in the tranny connected via a cable to the throttle quadrant.

The lockup is activated any time you go into 2nd gear or higher and the throttle position is less than 1/3 to 1/2 throttle position (33% to 50%). If you want to go to full manual control of the lockup, you're going to have to disconnect the tps altogether and or the computer and install a switch in the transmission ground position of your data port (I think it is the terminal on the far right of the OBD connector under the dash). The switch will override any command from the computer.

As I said in my previous post you are going to have to be vigilant as you don't want to have the tranny going through the gears with the convertor locked up. Your brake switch will still unlock the convertor as before. Ran the Buick with this setup for close to 100K without issue, after I got used to unlocking it when appropriate. You're also going to need a piece of electrical tape to stick over the check engine light

I would try a new TPS first. You may find your issues disappear. Try the cheap fix first.

Hope this helps.

Bill

Those TPS switches sure aren't cheap. I'm seeing prices of $100-$150+. Does that sound right?

By cheap fix, are you referring to the Bypass Switch? Unplug tps, connect wire to far right terminal of obd data port then to toggle switch on dash then to ground?