Skip the auto shop - Our mechanics make house calls

Can Sensors Be Cleaned or Do They Need to Be Replaced?

Warning light

In most cases, sensors for your automobile will need to be replaced if they fail, but depending on the type of sensor and its location or function, some can be cleaned and reused.

Sensors can come in many types and are used for a variety of systems on modern cars. We have sensors that communicate engine parameters, like coolant temperature, engine RPM, Oxygen in the exhaust, throttle position, engine speed by crankshaft rotation, and engine load via a MAP (manifold absolute pressure) or amount of airflow entering the engine MAF (Mass AIr flow sensor). MAF sensors have three different types starting with the vane air flow, the hot wire MAF and a Karman-Vortex MAF. We have sensors that caution us for blind spots or help us to park.

There are a host of sensors for the transmission which feedback information on road speed, and the internal parts of the transmission allowing a TCM (transmission control module) to select the proper gear at the proper time. Wheel speed sensors are used for ABS (antilock brake systems) and TPMS (tire pressure monitor systems) to keep an eye on the actual tire pressure and a torque sensor for steering assist and center for systems that add vehicle stability or VSC along with yaw rate and lateral acceleration sensors. AC pressure sensors control the operation of the AC system and the cooling fans and protect the system when the refrigerant charge is either too low, or the system pressure gets too high.

All of these sensors have one thing in common: they communicate to their respective computer or ECU (electronic control module) using electrical inputs. Some sensors use a change in their resistance to affect this input while others use magnetism to produce a small AC electrical output. Still others, like the knock sensor, report using a piezoelectric, sensor which generates its output based on pressure.

Sensors that are magnetic can sometime collect small particles of metal and cause a false signal. These sensors are very sensitive to the air gap between them and the tone ring or toothed gear which triggers the electrical reaction.

In most cases, there is little to clean and reuse as when a sensor goes out of calibration from wear or mechanical damage, or fails due to heat damage, the only repair is to replace them. In the case of a rain sensing sensor or a solar sun load sensor for the AC or perhaps a sensor for blind spot or curb detection, it is possible for them to get dirt or snow in bad weather covering them which could be cleaned.

Since the computers that rely on these signals treat all inputs as valid, when a sensor is faulty, replacement is usually the best option. Have the respective sensor checked by a professional to determine whether it can be cleaned or needs to be replaced.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Vacuum Brake Booster Check Valve Last?
The braking system on your car requires a lot of pressure. The vacuum booster is one of the main sources of this pressure. This booster will take the pressure that...
How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
P0121 OBD-II Trouble Code: TPS "A" Circuit Range Performance Problem
P0121 code definition Throttle Pedal Position Sensor/Switch (TPS) A Circuit Range Performance Problem...


Related questions

Q: How is the ABS sensor related to the driver side rear axle?

The speed sensor is important to all of the systems listed. The tire pressure system in your vehicle is a common basic type system. It uses the ABS sensor to measure the diameter of the tire. A tire with low...

Q: How many oxygen sensors do I have on my 2008 Cadillac Escalade EXT?

Hi there - your Escalade has 4 oxygen sensors total, 1 before each of the two catalytic converters, and 1 after each catalytic converter. Diagnostic codes are usually pretty specific as to which one is malfunctioning (i.e. Bank 1, Sensor...

Q: Rough idle and RPM fluctuation

This may be a sign of a faulty MAP sensor. The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses...