Recently inherited a 1986 IROC and working out issues with it. It had sat for a few years before I got it. Trying to set TPS voltage but lowest it will go is .96v. Swapped out TPS sensor with same results. Throttle plate is closed. What am I missing?

 

Test one without it being bolted to the tb, just connected to the wiring. Maybe its a limit in the range physically for some reason we can't see.

 

Was minimum idle speed set before tps was attempted to be adjusted?

 

xactly. The blades could be set too far open already

 

Also check to make sure the arm on the TPS sensor isn't bent or something.

 

disconnected the new one goes down to .62v, the old one was 1.6v disconnected

 

yes, blades are closed

 

Was just looking at that, tried some light filing on it to try and remove any corrosion build up

 

.62 vdc is removed from the tb ? Grey wire is 5v ?

 

What kind of meter is being used? Does it have a recent calibration label? Splitting measurements down to the millivolt range is no place for a "Boris" instrument that might be accurate to ±10V. That includes most of the automotive market tools, like the kind off the back of a roving ice cream truck, or those hanging on the wall at the parts chain stores that also sell oil treatments, synthetic car wash, and "Kamala-scented" air fresheners.