According to the wiring diagram black is ground.
I don't understand it but I think I have figured it out. My youngest daughters car is an 84 olds cultass. It has the 3.8 in it also and I got to thinking it should have a TPS and it did. So I looked in the manual to see if it is set up the same way and it is. I measured the voltage on hers at grey and it was 5 v as it should be, then on to the blue wire .5 v at closed throttle and 4.78 at wide open. It is the same type plug so I thought I would plug the sensor off the 95 on her car. Voltage was jumping around at closed throttle in the millivolt range but at wide open throttle it was 4.78 v. I think it is time to replace the computer. I'll find out after while when the parts houses open. I'll let you know. By the way Hotz28 I think my digital camera is broken, so I don't know of a way to put the picture on here but it mounts under the throttle body.
