How do you know if a throttle position sensor TPS is bad? Of course, some symptoms can tell you when a TPS may be bad. But these symptoms may come from other bad sensors, parts, or components. So you need to conduct some tests. The TPS connects to the throttle plate on the throttle body.
The position sensor has a variable resistance potentiometer or contact points, depending on model that sends a varying voltage signal to the Power Control Module PCM, your car's engine computer according to the position of the throttle plate. This plate rotates when you depress the gas pedal to allow more air to enter the intake manifold.
With the engine running, the position of the throttle plate along with other sensors tells the computer how much fuel the engine needs at any given moment. So, without the correct signal coming from the TPS, you begin to notice drivability problems.
Fortunately, it's not that hard to test the sensor. You can use the position sensor operating characteristics to test it using a digital multimeter DMM. If you haven't used a multimeter before, just take a look at the next video. In a couple of minutes you'll be ready to test the throttle position sensor in your car. And if you're looking for an inexpensive but good DMM for your toolbox—you need to use one for many DIY car family is not only blood quotes can find one at your local auto parts store or online.
The most typical failure you'll find on a TPS is wear, a short or an open on the circuit of the contacts or variable resistor. This guide will help you test the throttle position sensor in a few minutes and know whether you need to replace it. The most common TPS test is to measure for resistance ohms or voltage at the various positions, including throttle plate closed, half open and fully open. We'll use voltage to test the TPS here.
Open the hood and remove the air cleaner assembly where it connects with the throttle body. Inspect the throttle plate and the walls of the throttle body surrounding the throttle plate. Carbon buildup can prevent the throttle plate from closing properly and moving freely. Locate the TPS mounted on the side of the throttle body. The TPS is a small plastic block with a three wire connector. Carefully unplug the electrical connector from the TPS. Examine the electrical connector wires and terminals for dirt, contamination and damage.
Turn the ignition key to the ON position, but don't start the engine. And touch the black test lead from your DMM to each of the three electrical terminals of the TPS electrical connector. Make a note of the color of this wire. Turn the ignition key OFF. Connect the red test lead to each of the other two terminals.
One of the terminals should read 5 volts, or pretty close to it.You turn on the car and pull off the driveway when suddenly your car starts jerking like a wild mechanical bull!
You notice that your vehicle is lacking power and struggles to stay on. If you need to sell your car quick, it's easy to do online.
Symptoms of a failing tps?
Or read more info below. Enter your zip code below to get your FREE estimate and see how much your car is worth. Get paid the real cash value of your car in hours! If your throttle position sensor is giving you issues, then you may have the following questions. A bad throttle position sensor can cause other issues on your car if left unattended. That's right! If the sensor is faulty, it will cause your car to shake heavily.
Eventually, if this issue is left unattended it will put major stress on your motor and transmission mounts to the point where they will give out and will need replacement.
Get My Offer. A throttle position sensor is similar to the motor cortex in the human brain, it controls one of the most important components of the car that keeps your engine running like a throttle body.
Picture a little module in the car that reads how far down you have pressed the gas pedal. An engine needs two things to stay running which is air and fuel.
Normally a car will pick up air through the intake and passes it through the Mass Airflow Sensor. The air will travel up the intake and it will reach your throttle body.
In the old days, there was a wire attached to the gas pedal of your car and it would move accordingly to how you pressed it.
Nowadays there is an electric system that's far more efficient than the old ways but it can still have issues. When a TPS goes bad, then the car's throttle body won't function properly. It could either stay shut or it won't close properly which is a severe issue. If it stays shut then your engine is not going receive air and it won't start.
When the throttle gets stuck in an open position than your vehicle will receive too much air and cause it to have a high or fluctuating idle.
Acceleration issues: A bad TPS may cause all sorts of power issues. Your engine may start up but it will have little to no power and it causes it to shut off. On the other hand, it can also cause your car to have spontaneous accelerations even if you didn't step on the gas. Unstable Engine Idle: Faulty position sensors can cause sporadic idle conditions due to fluctuating airflow. If you see your car misfiring, Idling rough, or stalling out while you drive then you definitely want to have a professional check out that sensor.
Unusual fuel consumption: The TPS works alongside other sensors to ensure that your ride is driving smoothly and efficiently.The throttle position sensor TPS is part of your vehicle's fuel management system and helps ensure that the correct mixture of air and fuel is delivered to your engine.
The TPS provides the most direct signal to the fuel injection system of what power demands are being made by the engine. The TPS signal is continually measured and combined many times per second with other data such as air temperature, engine RPM, air mass flow, and how quickly the throttle position changes.
The collected data determines precisely how much fuel to inject into the engine at any given moment. If the throttle position sensor and its other sensor partners do their jobs correctly, your car accelerates, cruises, or coasts smoothly and efficiently, as you expect, while maintaining optimum fuel economy. The throttle position sensor can fail in several ways, all of which result in poor fuel economy at best, and performance limitations that may create a safety hazard for you and other motorists at worst.
It can also cause problems when changing gears, or setting base ignition timing. This sensor can fail gradually, or all at once. This is intended to at least allow a driver to get off a busy highway in a safer manner. Replacing the TPS will include clearing relevant fault codes, and may require software reprogramming of the new TPS module to match other engine management software.
This is all best left to a professional mechanic who can provide you with a diagnosis, and then install the correct replacement part. It may feel as though the car simply doesn't accelerate as it should, and jerks or hesitates as it picks up speed.
It may accelerate smoothly, but lack power. If these symptoms occur, there's a good chance you've got a problem with the TPS. When the car accelerates while driving, it usually means the butterfly valve inside the throttle has closed up and pops open suddenly when the driver presses on the accelerator. This gives the car an unintended burst of speed that occurs because the sensor cannot detect the closed position of the throttle. If you start to experience engine misfires, stalling, or rough idling when the car is stopped, it can also be a warning sign of a failing TPS.
You don't want to wait to get this checked out! If the idling appears off, it means the computer is unable to identify the fully shut throttle. The TPS can also send bad input that ends up stalling the engine at any time.
This is another failure mode of the TPS, which indicates that it is falsely limiting the power being requested with your accelerator pedal foot.1989 240sx Bad Bogging/Hesitation *SOLVED* * READ DESCRIPTION*
You may find that your car will accelerate, but not beyond a speed of 20 - 30 MPH. This symptom often goes hand in hand with loss-of-power behavior.
Have your vehicle checked for trouble codes to verify the source of the problem. The throttle position sensor is key to getting the desired power and fuel efficiency from your vehicle in any driving situation. As the symptoms listed above make clear, failure of this component has serious safety implications and must be checked out immediately by a qualified mechanic.
The most popular service booked by readers of this article is Fuel System Inspection. Our certified mobile mechanics make house calls in over 2, U. Fast, free online quotes for your car repair. Schedule Fuel System Inspection.A bad throttle position sensor is the last thing that you will ever wish to have on your ride. The purpose of a throttle position sensor is to keep your car working by controlling the throttle. With the passage of time, the sensor loses its efficiency and thus has to be replaced.
The important question is how to identify the throttle position sensor symptoms so that you end up replacing the right sensor?
Honestly speaking, it is not easy to detect throttle position sensor issues. However, there are specific throttle position sensor symptoms that will ensure you find the culprit. It senses the air, heat, and light, and sends the information to the ECM which adjusts the throttle and fuel supply accordingly. A faulty throttle position sensor sends incorrect information to the ECM resulting in various issues in the engine, its performance, and fuel economy.
Following is the list of the common symptoms of a faulty TPS. In most of the cases, all of these symptoms will show together making it easier to detect the faulty component. Jerking of the vehicle is the most common symptom of a bad TPS. These jerks can be experienced while accelerating or at high or low speeds. These are random jerks that will disappear at times. Idle surging can be caused due to other issues in the car but if it happens in conjunction with other throttle position sensor symptoms, the culprit is TPS.
At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surging. The check engine light will randomly turn on and off even if the car is running smoothly without any jerks and stalling. This is often the first ever symptom of a bad TPS. The engine can stall for no reason.
The engine can stall at high speed, at low speed, or even at idle. A faulty throttle position sensor will not let your car accelerate normally.
How to Check a Throttle Position Sensor
Hesitation in acceleration, acceleration surge at both high and low speeds, delay in acceleration, etc. As soon as you see a mix of these throttle position sensor symptoms, you should test the TPS and if it is not functioning properly, it has to be replaced.
Table of Contents.One of the more frequent problems with modern vehicles is a bad throttle position sensor TPS. The tiny thing that keeps your car working, often falls prey to regular wear and tear, and therefore must be taken care of.
Most modern-day throttle position sensors employ non-contact type elements, like two magnets and a Hall effect sensor. These sensors are less prone to wear, and thus last longer. It contains electro-mechanical parts, which are prone to weathering.
Would you like to write for us? Well, we're looking for good writers who want to spread the word. Get in touch with us and we'll talk It takes all the necessary measurements and sends it over to the Electronic Control Module. One unique thing about TPS failure is that all the symptoms may show up at the same time. The light is meant to tell you, the driver, that something is wrong with either a component of the car, or its sensor.
Another common symptom related to a bad TPS is the jerking of the car, especially when accelerating. Without proper inputs from the TPS, the on-board computer is unable to guide the engine to work at optimum levels. This problem usually comes in conjunction with the above one. Similar to getting jerks while accelerating, with a faulty TPS, the computer cannot tell if the throttle is fully shut when the car is idling.
This can happen anytime, without any kind of warning, while driving or idling. The TPS can give a bad input, prompting the engine to stall. This is a particularly hazardous situation.
All of this happens if the sensor is unable to detect the closed position of the throttle. The data provided by TPS is invaluable for proper starting, idling, and easy throttle response. Because of this, the following can occur: 1. Difficulty while changing gears. The fuel economy of the car drops drastically. Causes difficulty in setting base ignition timing of the car. Throttle Position Sensors are manufactured using switch, potentiometer, and combination designs.
If it is not adjustable, then it becomes mandatory that you check throttle stop and throttle cable adjustments. Their improper functioning could cause symptoms such as poor ignition, inefficient throttle response, or an idle stop. Switch and combination TPS are tested with an ohmmeter. In order to test a non-adjustable one, such as a potentiometer TPS, a voltmeter is used, like so: 1.
Disconnect the throttle sensor harness. Open the throttle valve manually and check the resistance changes between the terminal 1 and 2.A bad throttle position sensor will result in many serious problems on your car if you do not detect its failures soon. That is true. Therefore, learning some common throttle position sensor symptoms is very important to prevent any further damages. It transmits the most direct signal to the fuel injection system of what power needs are being created by the engine.
Its signal is calculated continuously and incorporated many times per second with other data such as air mass flow, engine RPM, air temperature, and how fast the throttle position changes. The collected data is used to determine exactly the amount of fuel delivered to the engine at any specific time.
If the TPS and other sensors work well, your car will accelerate, coast and cruise effectively and smoothly like what you want, while being at optimal fuel level. The TPS can be faulty due to many causes. When it happens, it leads to poor fuel economy and moreover puts you and other drivers around you in danger. It can also result in issues when setting base ignition timing, or changing gears. The TPS can gradually fail or all at once. This is made to enable a driver to get off a crowded highway in a safer way.
And when you detect there is a problem with your TPS, everything you need to do is to replace it immediately. When replacing the TPS, you have to clear related fault codes and may be need to reprogram the software of the new TPS module to fit with other engine management softwares.
The best way is bringing your car to a skilled mechanic who can inspect and install the right replacement part. Here are some common throttle position sensor symptoms or failing throttle position sensor to watch for:. A poor acceleration is one of the telltale symptoms of a bad throttle position sensor.
If you are experiencing any delay between the time you press the gas pedal and the time the vehicle moves further, you must take the car to an automotive expert. Inappropriate stalling is a clear sign that your vehicle has symptoms of bad throttle position sensor.
Although, stalling can be a sign of any other car problem as well, yet if it happens regularly, this can be the major reason. So do not ignore the issue. And, to avoid any major problem in future, gather some basic knowledge and maintenance tips for your car.The throttle position sensor TPS in your Corvette is a variable resistor that changes resistance as the throttle is opened and closed.
When the sensor develops a fault, some or all of the positions of the sensor will act as open circuits, causing a drop-out in the signal voltage to the on-board computer.
When the computer senses the loss of signal voltage, while the other sensors that it uses for engine load calculations indicate a load on the engine, it will store a diagnostic trouble code and turn on the "Check Engine" light on the dash.
Locate the sensor on the side of the throttle body near the front of the engine. Insert a straight pin into the electrical connector, alongside the dark blue wire in the center of the connector, until it contacts the terminal inside the connector.
Clip the red Positive meter lead to the straight pin and the black Negative meter lead to engine ground a bolt or other metal part on the engine. Turn the ignition key to "Run" but do not start the engine.
Open the throttle slowly, by moving the throttle cable with your hand, while watching for a drop-out in voltage. The voltage should rise smoothly from less than 2 volts Throttle Closed to 4. If the voltage suddenly drops to zero and then comes back, replace the sensor. This is a dynamic test, and it isolates the TPS from other things that could be causing the malfunction.
This article was written by the It Still Runs team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. To submit your questions or ideas, or to simply learn more about It Still Runs, contact us.
Step 1 Locate the sensor on the side of the throttle body near the front of the engine. Step 2 Clip the red Positive meter lead to the straight pin and the black Negative meter lead to engine ground a bolt or other metal part on the engine.
Items you will need Digital volt meter Straight pins. About the Author This article was written by the It Still Runs team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. Photo Credits corvette image by Julianna Olah from Fotolia.