Hey guys, thought I'd report back with an update. The parts were supposed to get here last Monday but they didn't show up until Wednesday. By then I was neck-deep in work. Had to go to a wedding last Saturday, and Sunday had to do rotors, pads and hub/bearing assemblies on my Tacoma. So long story endless, I didn't get back to the van until yesterday and today after work.
I swapped the new PCM in first. Then I swapped the harnesses. The new harness has two speed sensor connectors, one on a long leg and one on a short leg. The short leg only reaches the front sensor (on the extension housing of the trans) so I plugged it in there. The long leg is the only one that reaches the rear sensor so I plugged it in there.
problems I had before - which used to only happen one at a time - are now happening together. Argh! The speedo surges in park and neutral; and it reads super high when I'm rolling slowly in gear and barely touch the throttle.
To rule something out, I unplugged the short leg from the front sensor and left it disconnected. Then I swapped the long leg from the rear sensor to the front. That at least got rid of the idle surge in park and neutral. But the speedo still read super high. I would love to plug the short leg into the rear sensor but it doesn't reach. Doh! Do they make cable stretchers?
But seriously, does anybody have any ideas? It's as if the long and the short legs of the harness are reversed. Not to sound like an idiot but would unbolting and swapping the sensors themselves solve the problem? I'm thinking not because the signal comes from within the trans, right?
Is there such a thing as an extension cable? If not, could I have one custom made? I mean, it's only two wires...