Your explainations on the injector sneak paths make sense which is why I saw normal readings in the parts car...the injectors were all disconnected! There was likewise various resistence values as you indicated on every ECU pin. So, can I at least rule out the injector circuits of the harness?? I have the Volvo FI manual listing several diagnostic procedures, including the TPS. I'll check that tomorrrow to make sure the sensor is good.

Didn't get a chance to do much of anything today except start her up cold once. She started on the second crank but the idle was hunting up and down to the point of stalling. Eventually it went into its rough idle rythm. There's a test in the manual where the IAC is disabled and tested that I'll also cover.

I may even swap out the new IAC that was installed with the old one because I know how it behaved. But access is bad and I didn't have the forsight to angle the hose clamp screws facing an approachable direction. Although I've read that the IAC doesn't cause a rough idle, I'd like to check it anyway. New parts have been known to be bad.