What Does The Throttle Position Sensor Do? (1992-1993 3.3L V6 Pontiac Grand Am)

Your 3.3L V6 equipped Pontiac Grand Am is equipped with a throttle position sensor (TPS).

It's one of the critical engine management components that your vehicle's fuel injection computer uses to optimally and efficiently manage engine operation.

In this article, I'll answer some of the most commonly asked questions about the throttle position sensor (TPS).

You can find this tutorial in Spanish here: El Sensor TPS ¿Qué Es Y Para Que Sirve? (1992-1993 3.3L V6 Pontiac Grand Am) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.3L V6 Pontiac Grand Am: 1992, 1993.

What Does The Throttle Position Sensor (TPS) Do?

As you're probably already aware, the throttle plate opens and closes as you step on or step off the accelerator pedal.

It's the throttle position sensor's job to measure the amount the throttle plate opens/closes and then send this information to your vehicle's fuel injection computer.

Once the fuel injection computer receives this information, it can now manage a host of functions necessary to keep the engine running optimally and efficiently.

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

A bad throttle position sensor will not send any throttle plate angle information to the fuel injection computer.

As a result, the fuel injection computer will no longer be able to keep the engine running optimally.

Engine performance, driveability, and emission controls will suffer as a consequence.

The next section will go into what symptoms you'll see when the TPS fails.

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

A bad throttle position sensor will cause one or more of the following symptoms:

• Check engine light illuminated in the instrument cluster.
• TPS trouble codes registered in the fuel injection computer's memory:
  • Code 21: Throttle Position Sensor Signal Voltage High.
  • Code 22: Throttle Position Sensor Signal Voltage Low.
• 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?

The surest way to find out if the TPS is bad or not, is by performing a TPS multimeter test.

The TPS multimeter test is not a difficult test to do. In the next section, I'll go into some of the specifics of the TPS test.

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

Thankfully there is a method to the madness of testing any engine management component on your 3.3L V6 Pontiac Grand Am.

As I mentioned in the previous section, testing the throttle position sensor is pretty easy. The best part of all, is that you don't need any expensive diagnostic equipment.

In a nutshell, this is what the test involves:

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 The Throttle Position Sensor (3.3L V6 Pontiac Grand Am)

Can I Drive My Car 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.

Where Can I Buy The TPS?

The 1992 3.3L Pontiac Grand Am uses an adjustable TPS. The 1993 3.3L Pontiac Grand Am uses a non-adjustable TPS. They are not interchangeable.

The following links will help you to comparison shop for the throttle position sensor (of known professional automotive brands -NO knockoffs) for your 3.3L Pontiac Grand Am:

1992 Adjustable TPS

1993 Non-Adjustable TPS

More 3.3L Pontiac Grand Am Tutorials

You can find a complete list of 3.3L Pontiac Grand Am tutorials in this index:

• GM 3.3L Index Of Articles.

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

• How To Test Engine Compression Test (3.3L V6 Pontiac Grand Am).
• How To Test A Blown Head Gasket (3.3L V6 Pontiac Grand Am).
• How To Test The MAF Sensor (3.3L V6 Pontiac Grand Am).
• What Does A MAF Sensor Do? (3.3L V6 Pontiac Grand Am).