What Does The Throttle Position Sensor Do? (1989-1993 3.3L V6 Buick, Oldsmobile)

Your 3.3L V6 Buick (Oldsmobile) vehicle comes equipped with a throttle position sensor (TPS).

And it's one of the critical engine management components 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? (1989-1993 3.3L V6 Buick, Oldsmobile) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.3L V6 Buick Century: 1989, 1990, 1991, 1992, 1993.
• 3.3L V6 Buick Skylark: 1989, 1990, 1991, 1992, 1993.
• 3.3L V6 Oldsmobile Achieva: 1992, 1993.
• 3.3L V6 Oldsmobile Calais: 1989, 1990, 1991.
• 3.3L V6 Oldsmobile Cutlass Ciera: 1989, 1990, 1991, 1992, 1993.

What Does The Throttle Position Sensor (TPS) Do?

The throttle position sensor's job is to let the fuel injection computer know how much the throttle plate opens and closes as you step on or step off the accelerator pedal.

The fuel injection computer then uses this information to manage a host of functions necessary to keep the engine running optimally and efficiently.

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

When the throttle position sensor fails, the fuel injection computer is deprived of the throttle plate angle information it needs to manage engine operation.

The end result of this is that engine performance, driveability, and emission controls are going to suffer.

In the next section, you'll find a list of common symptoms you'll see when the TPS fails.

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

A throttle position sensor (TPS) that's no longer sending any throttle plate angle information to the fuel injection computer 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?

A throttle position sensor diagnostic test is required to find out if it's bad or not.

Testing the TPS is not difficult nor a complicated thing 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?

The first order of business, to find out if the throttle position sensor has failed on your 3.3L Buick or Oldsmobile vehicle, is to check for diagnostic trouble codes.

If indeed your vehicle has TPS trouble codes stored in the fuel injection computer's memory, then the next step is to test the sensor with a multimeter.

To be a bit more specific, this is the TPS test diagnostic flow:

1. Checking for TPS trouble code 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.

If the TPS has failed, its output voltage signal will not increase/decrease as you open/close the throttle plate.

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 Buick, Oldsmobile).

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 Throttle Position Sensor (TPS)?

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 V6 Buick (Oldsmobile).

1989-1992 Adjustable TPS

1993 Non-Adjustable TPS

NOTE: The 1989-1992 3.3L V6 vehicles use an adjustable TPS. The 1993 3.3L V6 vehicles use a non-adjustable TPS.

More 3.3L V6 Buick, Oldsmobile Tutorials

You can find a complete list of 3.3L V6 Buick and Oldsmobile 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 Buick, Oldsmobile).
• How To Test A Blown Head Gasket (3.3L V6 Buick, Oldsmobile).
• How To Test The MAF Sensor (3.3L V6 Buick, Oldsmobile).
• What Does A MAF Sensor Do? (3.3L V6 Buick, Oldsmobile).