Many thanks, Pennyman and Geezer. I'll try those approaches.

Another issue I have is setting the TPS. I hooked up the voltmeter to the ECU as instructed, but couldn't change the setting: no matter what I did, the setting remained the same...4.95. It's supposed to read 0.4 or some such thing. Perhaps the meter setting was wrong, though I tried various settings with the same results. The TPS is only a year old. Fooling with that ECU is my least favorite task on this truck. I just don't understand it, and it's a bitch to get to. I finally just set the TPS at a midway point ( biased toward -) and called it a day