Servo Actuation Test
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 1992 Pontiac Grand Am, 1992 Oldsmobile Achieva, 1992 Buick Skylark, 1991 Pontiac Grand Am, and 1991 Oldsmobile Cutlass Calais. However, it is still accessible from the selected car via links, so may be relevant.
- With ECM connector plugged in, disconnect servo harness connector. Using a fused jumper wire, connect terminal "C" (servo side) to ground. See Figure . Using another (non-fused) jumper wire, connect battery voltage to servo terminal "A" (servo side).
- Start engine for one minute and shut off. Using a jumper wire, connect servo terminal "E" to battery voltage. If servo pulls throttle cable and holds it in, go to next step. If servo does not pull and hold throttle cable, check vacuum lines for leaks or restrictions. Check vacuum release valve. If release valve and all vacuum lines are okay, replace servo.
- Tap brake pedal. If servo releases throttle cable, go to next step. If servo does not release throttle cable, check vacuum line-to-vacuum release valve for kinks or restrictions. If vacuum line is okay, replace vacuum release valve.
- Disconnect fused jumper wire from servo terminal "C". See Figure . Start engine for one minute and shut off. Reconnect fused jumper wire between ground and servo terminal "C". After servo pulls throttle cable, disconnect jumper wire from servo terminal "A".
- If servo does not release throttle cable, replace servo. If servo releases throttle cable, replace ECM (2.5L models) or cruise control module (2.3L and 3.3L models).