I have a 95 chevy s10 zr2 with a4.3l. I have codes for tps. I have good ground ,5 volts gray wire when key is on.when sensor is on truck ,volts on blue wire is .23 and drops to .02 as throttle is opened, but if take sensor off but still plugged in (sweep test) I get.5 volts up to 5 volts. Can anyone help

Have you checked the 5v feed as you crack the throttle? Is the throttle closing too far?

It may just be a bad spot on the sensor that you happen to be at the point the sensor rests at on the truck.

I did check 5v all good,I get good volt reading when sensor is off truck, but once I put on then weird volt readings

Are you installing it correctly? You can't just plop it on and screw it in. It has to be put on one way, then rotated, then screws go in,.

I tried rotating sensor and butterfly and still reads weird, but when I take it off sweep test is fine

This makes absolute no sense at all.......

If you are installing it correctly(you are sure the tab is engaging the TPS correctly?), then you have a bad male/female connection in the harness connector, or you have a broken wire inside the insulation of the wire.....

My vote is a fiddly sensor, which would still be corrected by replacement.

the butterfly rotates clockwise (when looking at it) sensor rotates clockwise so to me that they are working against each other