What Does The Throttle Position Sensor Do? (Ford F150, F250, F350)

Your F-series pickup comes equipped with a throttle position sensor (TPS). It's a very important engine management system component. So when it fails, engine performance is going to suffer.

In this article, I'm gonna' answer some of the most frequently asked questions about the throttle position sensor. I've also included the links to 2 TPS test tutorials.

APPLIES TO: This tutorial applies to the following vehicles:

• Ford Bronco: 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996.
• Ford F150: 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996.
• Ford F250: 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997.
• Ford F350: 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997.

What Does The Throttle Position Sensor (TPS) Do?

The sole purpose of the throttle position sensor (TPS) is to report to the fuel injection computer how much the throttle plate opens/closes as you step on or step off the accelerator pedal.

With this information, the fuel injection computer can maintain the engine running efficiently and optimally.

What Happens When The Throttle Position Sensor (TPS) Goes Bad?

When the throttle position sensor goes bad, one of two things happens:

• The fuel injection computer no longer receives any throttle plate angle information.
• The fuel injection computer receives incorrect throttle angle position information.

Both scenarios are not good, since they'll cause engine performance problems.

In the next section, I'll list some of the symptoms you'll see when the throttle position sensor has gone rogue.

What Problems Can A Throttle Position Sensor (TPS) Cause?

Since the throttle position sensor is a critical component of the engine management system on your F150 (F250, F350), when it fails engine performance is definitely going to suffer.

You'll see one or more of the following symptoms:

• Check engine light illuminated in the instrument cluster.
• On OBD I equipped pickups, you'll see one of the following TPS trouble codes registered in the fuel injection computer's memory:
  • Code 23: Throttle Position (TP) Circuit Performance Problem.
  • Code 53: Throttle Position (TP) Circuit High Input.
  • Code 63: Throttle Position (TP) Circuit Low Input.
• On OBD II equipped pickups, you'll see one of the following TPS trouble codes registered in the fuel injection computer's memory:
  • Code 121: Throttle Position (TP) Circuit Performance Problem.
  • Code 122: Throttle Position (TP) Circuit Low Input.
  • Code 123: Throttle Position (TP) Circuit High Input.
• Engine hesitates when you step on the accelerator pedal.
• Lack of power when accelerating the vehicle.
• Bad gas mileage.
• Engine idle either too high or too low.
• Rough engine idle.
• The engine may start and immediately stall.
• The engine cranks but does not start.

How Can You Tell If The Throttle Position Sensor (TPS) Is Bad?

To find out if the throttle position sensor has failed on your F-series pickup, you'll need to test it. This is the only way to find out if it is truly bad or not.

Thankfully, the throttle position sensor can easily tested with a simple multimeter. You don't need any expensive diagnostic equipment to test the TPS.

The next section explains what's involved in testing the throttle position sensor.

How Can I Find Out If The Throttle Position Sensor (TPS) Is Bad?

As I mentioned earlier, the throttle position sensor can easily tested with a simple multimeter.

The TPS multimeter test involves the following steps:

1. Checking for TPS trouble codes stored in the fuel injection computer's memory.
2. Making sure that the TPS is getting power.
3. Making sure that the TPS is getting Ground.
4. Making sure that the TPS signal increases/decreases as the throttle plate is opened/closed.

You can find the throttle position sensor test explained in a step-by-step manner here:

• How To Test: Throttle Position Sensor (1988-1995 Ford 4.9L) (at: troubleshootmyvehicle.com).
• How To Test The Throttle Position Sensor (Ford 5.0L, 5.8L).

Can I Drive My Pickup With A Bad Throttle Position Sensor (TPS)?

In most cases, the engine performance problems caused by a bad TPS will not allow you to safely drive the vehicle.

But, even if the vehicle can be driven, you should avoid doing so.

More Ford F150, F250, F350 Tutorials

You can find more tutorials Ford F150, F250, and F350 in the following index:

• Ford 4.9L, 5.0L, 5.8L Index Of Articles.

Here's a sample of the tutorials you'll find in the index:

• How To Test The Ford Ignition Control Module (Distributor Mounted).
• How To Test The Ford Ignition Control Module.
• Throttle Position Sensor (TPS) Test (Ford 5.0L, 5.8L).
• How To Test The Ford Mass Air Flow (MAF) Sensor.