Your Buick Park Avenue TPS is otherwise known as the throttle position sensor. It’s primary job is to read the angle of your throttle blade and transmit the data to your Buick Powertrain Control Module. Over time your throttle position sensor can go bad, causing your Buick to run poorly.
Today I’ll be showing you how to test the Park Avenue TPS Sensor in a 3.8 liter engine. This Buick is a 2000 Ultra model, which also happens to be supercharged. Because of the nature of this 3.8 liter supercharged engine, a failing throttle position sensor can cause serious driveability issues.
The throttle position sensor can send bad signals to your PCM, which can cause symptoms you may misdiagnose. Your throttle position sensor is mounted on the opposite side of your throttle blade, and mounted facing towards the firewall.
Symptoms of a failed Buick Park Avenue TPS Sensor
When your Park Avenue TPS sensor starts going south, you will can see several symptoms arise. Some of these are annoying problems, but some of the more severe symptoms can cause premature engine failure or transmission problems.
- Inconsistent throttle response
- Harsh shifting
- Ignition pre-detonation
- Surging engine speed or engine revving on it’s own
How to test your Park Avenue TPS for Power
To begin testing your Park Avenue TPS sensor, you must turn your ignition to the “ON” position. Open your Buick hood and locate the throttle position sensor, again this unit is on the throttle body.
Because our test vehicle is a 2000 Buick Park Avenue Ultra, the TPS sensor is under the Supercharged engine cover. Remove this cover to expose the throttle body and the three pin sensor.
You will be using an automotive multimeter to test the DC voltage of PIN 3. This is a GRAY wire and you will be checking for voltage at this wire. If you have power at this wire, you will be checking for ground signal next.
The ground wire for this unit is PIN 1, which is a black wire. Once you have tested for a low reference ground signal at this wire, you should know that your Park Avenue TPS has everything it needs to work.
Testing your Park Avenue TPS Signal
Now that you know your throttle position sensor has power and ground, the next step is to check the signal. The signal wire for your Park Avenue TPS Sensor is PIN 2, the middle wire which is a DARK BLUE wire.
Your throttle position sensor must be plugged in to get this part of our How To DIY article. You can use a backpin to measure the signal from PIN 2, or pierce the middle wire once you are ready. Don’t start your 3.8 liter engine for this part of the test, simply leave the key at the “ON” position.
Now with the throttle plate completely closed, you will need to measure the middle pin. This wire should be transmitting between .6-.8 volts of DC signal to your Buick Powertrain Control Module. Remember that this is with your throttle completely closed.
Have a friend sit in the car and depress your Buick accelerator pedal all the way down. This should open the throttle plate all the way open, which should scale the throttle voltage up. Now your Park Avenue TPS should be reading between 4.5-4.9 volts of DC signal.
Your results in your Buick Park Avenue may vary of course, but the signal should be around this range. Because your throttle position sensor works on a 0-5 volts DC signal, if you find your base voltage too low, or the fully open throttle reading too high your TPS must be replaced.
You now know how to test your Park Avenue TPS sensor. If you have any questions or comments please leave them for us below!
