How To Test The Throttle Position Sensor (Ford 5.0L, 5.8L)

Accurately testing the throttle position sensor (TPS) on your Ford v.0L or 5.8L pickup, van or SUV is not hard to do.

In this 'How To' tutorial, I'll show you how to exam the TPS with a multimeter and find out if information technology's actually bad or not.

This is an on-car test of the throttle position sensor. You'll notice that the photos prove the TPS out of the car, but this is but to get in easier to explicate the test.

En Español You can discover this tutorial in Spanish here: Cómo Probar El Sensor TPS (Ford five.0L, v.8L) (at: autotecnico-online.com).

Symptoms Of A Bad Throttle Position Sensor

The i affair that yous can definitely count on, when the TPS fails, is the check engine light shining nice and brilliant to let you know that there's a diagnostic trouble code stored in the fuel injection computer. Here are some specific symptoms you'll run into:

  1. TPS diagnostic problem codes (DTCs) stored in the vehicle's estimator'due south retention.
    • Code 23: Throttle Position (TP) Circuit Performance Problem.
    • Code 53: Throttle Position (TP) Circuit High Input.
    • Lawmaking 63: Throttle Position (TP) Circuit Low Input.
    • Code 121: Throttle Position (TP) Excursion Performance Trouble.
    • Code 122: Throttle Position (TP) Excursion Depression Input.
    • Lawmaking 123: Throttle Position (TP) Circuit High Input.
  2. Really bad gas mileage.
  3. No power as you accelerate the vehicle.
  4. Hesitation when you pace on the accelerator pedal.

At that place are times when the ECM (Electronic Control Module = Fuel Injection Estimator) will remember the TPS has failed when information technology hasn't. This usually happens when the ECM spits out several diagnostic trouble codes at once and so what will save you time, coin and the frustration of replacing good parts, is to examination the throttle position sensor.

What Tools Are Needed To Test The TPS?

The almost important tool you'll need is a multimeter. The multimeter can be an analog or digital ane (don't have a digital multimeter? Demand to buy one? Click hither to see my recommendations: Buying A Digital Multimeter For Automotive Diagnostic Testing).

You lot'll also need:

  1. A helper.
  2. Wire piercing probes
    • Since the TPS has to be tested in action (and with the key in the ON position), you lot'll need to pierce the wires with something to get to the bespeak inside the wire.
    • To see what a wire piercing probe looks similar, click here: Wire Piercing Probe.

A generic scan tool that can read OBD I diagnostic trouble codes does come in handy, only the scan tool won't help y'all test the TPS and therefore you won't need it to apply the exam info in this tutorial (the exam in this tutorial will help you test the TPS without a scan tool).

Circuit Descriptions Of The Throttle Position Sensor

Circuit Descriptions Of The Throttle Position Sensor. How To Test The Throttle Position Sensor (Ford 5.0L, 5.8L)

Beneath are the job descriptions of the three wires that stick out of the TPS:

  1. Circuit labeled ane:
    • five Volts from PCM.
    • This wire is Red in colour.
  2. Circuit labeled ii:
    • Throttle Position (TP) Signal Circuit.
    • This wire is Blackness in color.
  3. Circuit labeled 3:
    • Sensor Ground Excursion.
    • This wire is Greenish in color.

You'll need to keep one very important matter in listen and that'southward that these iii circuits go directly to the ECM. So you need to be careful not to brusk these wires to power (12 Volts) or you will fry the fuel injection computer.

How Does The Throttle Position Sensor Work?

The TP sensor's job is to inform the ECM how much the throttle plate is opening or endmost. It'due south able to practice this because it's mounted on the throttle body and straight linked to the throttle plate shaft. So when the throttle plate shaft rotates, a wiper inside the TPS also moves (along a curved resistor) and is able to send a variable voltage signal to the ECM.

OK, in a nutshell, when you crank and offset your Ford vehicle:

  1. The throttle position sensor gets 5 Volts and Ground from the ECM.
  2. As the engine in your pickup or van idles (and the throttle plate is airtight), the throttle position sensor sends the ECM a voltage indicate of well-nigh 0.nine to one Volts.
  3. In one case you step on the accelerator pedal, the throttle plate opens and since the TPS is connected to the throttle, it starts to measure how much it opens.
  4. When the throttle plate opens, the voltage increases. When the throttle plate closes, the voltage decreases.
  5. The ECM is then fed this changing voltage.
  6. Once the PCM gets this voltage, it does its little song and trip the light fantastic and starts to calculate fuel injection, ignition timing, transmission shift points, etc. in conjunction with the MAP sensor, PIP sensor, engine coolant sensor and and then on and on.
  7. This procedure of informing the ECM of throttle plate angle goes on the whole time the engine is running.

Pretty unproblematic stuff, no? Well testing it is just as simple. Since you'll be working in the engine compartment, no need to tell you (just I'm gonna' tell you anyhow) to be alert and exist very careful. Employ common sense and take all necessary safety precautions. OK, allow'southward get this show on the route, go to: TEST 1: Testing The TP Signal With A Multimeter.

Where To Purchase The TPS And Save

The TPS isn't also expensive, if you buy it at your local auto parts. Check out the following links. I think they'll relieve you lot a few bucks:

Not sure if the above TPS fits your particular Ford? Don't worry, once yous get to the site they'll make certain it fits by request you the specifics of your particular Nissan vehicle. If it doesn't fit, they'll notice you lot the right one.