How to Test the Throttle Position Sensor
(2.3L Ranger, Mustang, B2300)
-Part I-


In this tutorial, I'll help you troubleshoot the Throttle Position Sensor (TPS) on your 2.3L Ford Ranger or 2.3L Ford Mustang.

You don't need a Scan Tool or any other expensive diagnostic tool to find out if it's BAD or not.

I'll explain the entire test in a step-by-step way. By the way, this Throttle Position Sensor Test is for:

Symptoms of a BAD Ford TPS

The very first thing you'll notice, when the TPS goes BAD on your 2.3L Ford Ranger or Mustang, is the Check Engine Light shining nice and bright. You'll also see:

What Tools do
I Need for the TPS Test?

I can tell you right off the bat that the one thing you don't need is a Scan Tool. You need a few basic things and they are:

You’ll need a helper to help you to perform the test steps in TEST 1. Other than that.. nothing else is needed.

Circuit Descriptions: Ford TPS


The Throttle Position Sensor (TPS) on your 2.3L Ford Ranger (or 2.3L Ford Mustang or Mazda B2300) has 3 wires sticking out of its connector.

Each wire has a specific job to do and below you’ll find out what each wire (circuit) does.

One very important thing to know is that all three circuits start and end at the PCM (Powertrain Control Module=Fuel Injection Computer) or vice-versa... depending on how you look at it.

NOTE: When checking for the Signals the wire carry, you should not probe the front of the TP Sensor’s connector’s terminals. I suggest you use a Wire-Piercing Probe (click here so that you can see what one looks like: Wire Piercing Probe) to connect to your Multimeter.

Another important tip... since these three circuits go directly to the PCM, you need to be careful not to short these wires to Power (12 Volts) or you’ll fry the PCM.

How Does the
Throttle Position Sensor (TPS) Work?

The Throttle Position Sensor’s job is to measure the angle of the Throttle. So here, in a nutshell, is how the TPS on your Ford 2.3L Ranger or Mustang (Mazda B2300) works when you crank and start the Engine:

Pretty easy stuff? The cool thing is that the Tests to check out the TP Sensor’s performance are as easy too. Now, since you’ll be working in the engine compartment take all necessary safety precautions and use common sense. OK, enough of my yakking, let’s get this show on the road... go to TEST 1

Ford Vehicles:

  • Mustang 2.3L
    • 1991, 1992, 1993
  • Ranger 2.3L
    • 1993, 1994

Mazda Vehicles:

  • B2300 2.3L
    • 1994