Toyota is among the brands that produce some of the best vehicles in the market. The vehicles are not only affordable but are also effective when it comes to performance and fuel economy. But, despite being rated among the best, Toyota vehicles sometimes suffer from various throttle position sensor issues that cause problems such as acceleration and idling issues. So, in this guide, we’re going to learn how to reset the throttle position sensor in a Toyota.
Why is it important to remedy this problem on time? You see, the TPS, or rather the throttle position sensor is a small but highly significant part that handles a key assignment in your car’s fuel management system.
In case it’s faulty, this part can cause noticeable and sometimes severe consequences such as poor fuel economy and deteriorated performance of the engine. So, to avoid these failing signs, it’s important that you reset the TPS in your Toyota. That said, this guide will walk you through a very detailed procedure on how to reset your car’s TPS.
What is a Throttle Position Sensor and How Does it Work?
The TPS is a vital sensor that sits next to the throttle body on top of the butterfly shaft. This sensor resembles a black cap with a hose and is so small making it hardly noticeable. In fact, this sensor can’t be reached easily by hand and will need a special tool to get it.
Now, the TPS is tasked to handle one of the major roles in the engine. Its work is to monitor the movement of the gas pedal and how fuel and air are combusted in the combustion chamber. From there, it sends data to the car’s ECU to ensure fuel and air are mixed in the correct ratios to maintain combustion.
Throttle position sensors come in two major variations. There’s the hard-wired version that’s common in old vehicles and the magnetic field variation that’s common in modern cars. With the hard-wired TPS, the sensor monitors the amount of air flowing through the intake manifold once it opens (as you accelerate).
On the other hand, the modern version observes changes in the magnetic field as you accelerate. Due to the complexity of the technology, modern TPS sensors are hard to repair meaning you must replace them completely once they’re faulty.
Symptoms of a Failing Throttle Position Sensor
Now that you’re aware of what the TPS is and how it works, this guide will now try to list some of the common signs of a faulty TPS. At least by noting these signs, it will be easier for you to ascertain that indeed the TPS is the one at fault.
Check Engine Light:
The first obvious sign of a failing TPS is the presence of a yellow or orange check engine light on the dash. In most cases, a check engine light indicates a severe problem with one of the engine components. Since the TPS is among the vital engine components, this might be a sign that you’re dealing with a faulty TPS.
Another clear sign of a failing TPS is irregular idle revs when you turn on the engine. Here, you’re likely to hear the engine sounding as if it wants to turn off or sound as if it’s struggling. Other times, you’re likely to see the rev gauge fluctuating. If this is what you’re seeing, then it’s likely the TPS is failing.
Low Fuel Efficiency:
Earlier on, we mentioned that the TPS’s duty is to monitor the ratio of fuel/air in the combustion chamber. In case this sensor fails, then it means it will send false data to the ECU. As a result, the ECU will direct the injectors to supply excess fuel to the combustion chamber leading to fuel wastage.
If you’re experiencing inefficient acceleration or poor response from the gas pedal when driving, then there’s a high chance the TPS is failing. Here, you enjoy a smooth acceleration that later turns into a series of dips and surges. In most cases, you’ll experience loss of power, surges when accelerating, delays when shifting gears, and hesitation when you try to accelerate.
How Do You Effectively Set Your Throttle Position Sensor
So, we’ve discussed some of the common signs of a failing TPS. We’ve also discussed what it is and how it works. In this last section, we’re going to look at how to reset the TPS on your Toyota.
First Throttle Sequence
The first method we’re going to outline is quite simple as it doesn’t demand any tools. This method is considered particularly useful if you’re dealing with a dead battery or a battery that needs to be jumpstarted. So, to reset your TPS using this method, follow these steps.
- Step One: In the first step, you’ll need to start the engine to warm it up to optimal temperature. You can leave it to idle for a few minutes or even press the gas pedal to prevent it from stalling.
- Step Two: Once the car is ready, it’s now time to start the process. Insert the key to the ignition and turn the engine on.
- Step Three: Wait for a few seconds and turn the engine off.
- Step Four: Turn the engine on again and wait for another few seconds before turning it off.
- Step Five: Next, turn on the ignition and this time, crank the engine and don’t forget to pull the parking brake.
- Step Six: Turn the gear shift to drive and wait for at least 5 to 10 minutes.
Second Throttle Sequence
The second reset method is the one that doesn’t require any pre-warming of the engine. This method is particularly effective if you own a Toyota Tacoma model that was manufactured between 2005 and 2015. Here are the steps to consider.
- Step One: Start by turning the ignition to the on position.
- Step Two: Leave the engine on and don’t crank it.
- Step Three: Press the gas pedal slowly and hold it to position for around 3 to 4 seconds before releasing it.
- Step Four: Turn the ignition off and pull out the keys. Wait for around 10 minutes.
What if None of the Methods Work?
Although we’ve discussed two of the common methods you can use to reset your car’s TPS, there are times when these methods fail. Sometimes, these methods can fail due to your car’s specific model and the type of TPS you’re dealing with (in terms of timings ad sequences). Although it’s recommended to have the TPS replaced, we’ve outlined two different methods you can consider before you finally decide to replace the sensor.
Battery disconnection is one of the simplest methods you can consider if you want to reset your car’s TPS. This method is usually a two-step process that’s very easy to accomplish.
- Step One: So, here, you need to start by opening the hood to locate the car battery.
- Step Two: Once you’re done, use the appropriate wrench to disconnect the battery cables.
- Step Three: Once you detach the cables from the battery, leave it for a few minutes, most probably 5 to 10 minutes before re-attaching them back. By doing this, you allow the car’s electronic system to discharge and then recharge. Actually, it’s more like rebooting the car’s electronic system.
Resetting the Fuse
In this second method, we’ll be resetting the TPS by removing the fuse and then putting it back. In most cases, this approach is rarely used due to its complexity. Since you must identify the location of the fuse box, it’s always important to refer to your car’s manual.
- Step One: So, as usual, use the manual to locate the position of the corresponding fuse.
- Step Two: Next, use a fuse puller to pull out the fuse. Once it’s out, inspects it keenly to see whether it’s damaged. If it’s in good condition, then you can put it back.
As you can see, the TPS is one of the vital components in your car’s engine. In case it malfunctions, you’re likely to experience various symptoms that can range from mild to severe. In this guide, we’ve highlighted some of the common symptoms that point to a malfunctioning TPS.
From there, we’ve suggested two methods you can use to reset a failing TPS. In case these methods fail, we’ve added two bonus methods you can consider. With these methods at your disposal, it will be much easier for you to fix some of the problems you might be experiencing with your TPS.