top of page

How to Test and Adjust your Mercury EFI TPS

Your Throttle Position Sensor (TPS) TPS can be adjusted using a digital

meter and our is available for sale on this site. Analog (needle) type may be used although it may be difficult to read the low voltage setting accurately with most meters.

1. Disconnect TPS from the EFI harness.

2. Connect digital using TPS Test Lead Assembly (a) (P/N 91-816085) between TPS connector (b) and EFI harness connector (c). Set voltmeter to 2 DC volts.

3. Disconnect the TAN/BLACK engine head temperature sensor leads located on the port cylinder head.

4. Turn the key to the “ON” position.

5. Loosen screws (1) securing TPS to manifold.

6. Rotate TPS fully clockwise (holding the throttle shaft in a closed position). Your voltmeter should read .200 - .300. If the readout is not within specifications, adjust TPS to obtain a readout of .240 - .260.

7. Tighten TPS screws to 20 lb. in. (2.0 N·m) holding the correct tolerance.

8. Disconnect the remote control cable from the throttle lever.

9. Slowly move the throttle lever to the full open position while monitoring the voltage reading. The voltage reading should increase and decrease smoothly.

10. Set the volt meter to 20 DC volts. Maximum voltage reading at full throttle is approximately 7.46 volts.

11. Remove the test leads and reconnect the TPS harness to the EFI harness.

12. Reconnect TAN/BLACK engine head temperature sensor leads located on the port cylinder head.

NOTE: If the engine appears to run too rich or too lean, TPS can be readjusted. Decreasing voltage yields a leaner mixture. Increasing voltage yields a richer mixture.

241 views0 comments

Recent Posts

See All


Obtuvo 0 de 5 estrellas.
Aún no hay calificaciones

Agrega una calificación
bottom of page