Find out how to check the TPS on a 90 Honda Accord. The throttle positioning sensor (TPS) on your Accord is an electronic device that monitors the position of the throttle. This information is fed to the car’s computer, which is then used to optimize both performance and fuel economy. The TPS is also necessary for proper startup, idle and throttle response. Over time, the TPS can wear itself out, leading to several drivability-related issues.
Symptoms of a bad TPS include:
- Idle surging
- Bucking and jerky throttle action
- Hesitation upon acceleration
- Sudden surge of speed while driving
- Random engine stalling
- Sudden poor fuel economy
The good news is that the TPS on the 90 Honda Accord can be checked and if needed, adjusted back to the proper spec. The bad news is that the TPS was initially intended to be non-removable; therefore the sensor is attached to the throttle body by two shear-head screws in order to prevent tampering. Nevertheless, the sensor can be loosened and adjusted with a little extra work involved.
What you’ll need:
- Hammer and chisel
- New screws to replace the old shear-head screws
- Phillips head screwdriver
- Locate the TPS. The TPS is located on the throttle body of the Accord, which is towards the rear of the engine on the left side, just ahead of the air intake hose.
- Loosen the TPS. The TPS is secured to the throttle body by two shear-head screws. In order to loosen these screws, you’ll need a hammer and chisel. Place the chisel at the edge of the screw and lightly tap until the screw is loose. Then you can remove them by hand. Replace these screws with M5x16x0.8 sized screws, available at your local hardware store.
- Check the TPS. Check the connectors for any rust, dirt or other imperfections. Then reconnect the cable to the TPS and measure the voltage with your voltmeter. Make sure the new screws are in place and lightly tightened, just enough so you can still move the TPS around.
- Calibration procedure. Look at your TPS connector cable. You should see three wires. Locate the red wire – this is where the red pointer on your voltmeter will go. Set your voltmeter to 20v and position the red lead to probe the red wire and place the black lead to the ground on the battery. Turn the ignition to the ON position without starting the car, then go back to the engine bay and check the readings on the TPS. Start turning the TPS back and forth in small increments until the reading on the voltmeter reads .50v. Once this reading is achieved, carefully tighten the screws, making sure the TPS remains at .50v. After the TPS is back in place, disconnect and reconnect the negative cable on the battery. This will reset the car’s computer, allowing it to adapt to the changes made.