1993 Chevy S-10 voltage meter surging truck wont stay runni

TGJEFLE

MEMBER
1993 CHEVROLET S-10
6 CYL
2WD
MANUAL
118,000 MILES

My 93 chevy s-10 started running funny one day, I looked at the dash and the voltage meter was pegged to the top. Truck ran really rough till I got it home then it would only stay running if I throttled it for a bit then it would sputter and stall out.I was told it maybe my volage regulator. I changed it, my alternator, and battery and still the same result. Another person told me to check my trottle positioning sensor but im not too sure how to do that or how many ohms it should have thanks for looking

1 Reply

PEAR69

MECHANIC
1,482 POSTS

Your throttle position sensor is a variable potential meter. This simpley means that the voltage increases and decreases with the throttle position. To test it you must back probe the variable wire. The TPS has 3 wires on it one is a ground(no voltage) one is a 12 volt feed(12 volts constsntly with the ignition on) one is the varible wire(goes from zero volts to a higher voltage according to throttle position. I think this wire is blue. Get a volt meter and back probe this wire with the positive probe and ground the other probe to the engine. With the ignition on (motor could be off or on--safer off) open the throttle and observe the meter. The voltage should steadily and smoothly increase and decrease according to throttle position.