The lambda probe is an important piece of the car engine; it is part of the emission control system, is the size of a spark plug and tests the oxygen levels in the exhaust gases. When dirty it triggers the engine light to come on and could burn more fuel. If you are concerned that this sensor is dirty, you can clean it by removing it from its housing and letting it soak in gasoline overnight.
Steps
Part 1 of 3: Locate the Lambda Probe
Step 1. Protect your hands and eyes
Since you have to work with gasoline and various parts of the car, it is essential to protect yourself from possible injuries. Before you lift the car and look for the probe, put on a pair of sturdy gloves to repair your hands and wear eye protection or goggles in case gasoline or WD-40 splash dangerously close to your eyes.
You can purchase both protective devices at hardware or home improvement stores
Step 2. Jack the vehicle up
To remove the lambda probe you need to access the lower portion of the engine compartment. Before proceeding, make sure that the car is parked on a flat lay-by, that you have engaged the parking ratio (if the transmission is automatic) or first gear (if the transmission is manual) and that you have activated the handbrake.
You can buy a jack at any auto parts store; Talk to the clerk and let him know which car model you have so he can recommend the appropriate tool
Step 3. Identify the lambda probe
Depending on the manufacturer and the vehicle model, there may also be different sensors. Consult the machine manual for the exact location of each probe. All models are equipped with at least two probes: one in front of the catalytic converter and one inside the exhaust manifold. If the car has more than one manifold, there is likely to be a probe in each of them.
The sensor resembles a spark plug and is approximately 5 cm long. One of the ends has the hexagonal shape to allow the insertion of a wrench, the other is threaded and fits into the vehicle
Part 2 of 3: Remove the Lambda probe
Step 1. Spray the probe with the WD-40
Since this element is rarely disassembled, it is likely to be stuck; to loosen it, sprinkle it with a lubricant (such as WD-40) and wait 10-15 minutes. Meanwhile the oil penetrates and loosens the tightening facilitating removal.
If you don't have a can of this product, you can buy it at any hardware store or auto parts store
Step 2. Fill a bucket or industrial container with gasoline
While you wait for the WD-40 to do its job and lubricate the sensor thread, you can begin the next step in the process. Fill a large bucket or plastic container with gasoline and place it near the car. Once the probes are removed, you can clean them by immersing them in fuel.
- Check that the bucket or container you have chosen is built to safely contain the gasoline; not all materials are resistant to this substance.
- If you are buying the bucket at the hardware store, ask the clerk to recommend a sealable model suitable for holding gasoline.
Step 3. Unscrew the sensor from its housing
For this you need a sturdy wrench; at this point all the probes present should be well lubricated and loosened, unscrew them firmly with the tool. While removing them, do not rest the sensors on the ground and prevent them from getting dirty; put them in a clean container, such as a plastic bowl or a clean, flat surface of the car.
- If you don't know the size of the wrench to use, you can evaluate it by trying to engage a medium-sized tool over the sensor head. If the first key isn't suitable, switch to a larger or smaller one as needed.
- Alternatively, use an adjustable one.
Part 3 of 3: Clean the Lambda probe
Step 1. Immerse all sensors in the pail with gasoline
Once disassembled from the vehicle, transfer them to the industrial container or bucket where you previously poured the fuel; giving it the right time, this substance is able to clean the mechanical parts. Check that each probe is completely below the liquid level and that the liquid does not splash out of the container or onto your hands.
Do not smoke, do not light a candle, and do not use any open flame when working near gasoline
Step 2. Cover the bucket with the lid
Since gasoline is flammable, it is important to seal the container to prevent the vapors from igniting and to prevent stray animals from accessing the liquid; if the industrial container has a lid, you can use it to cover the gasoline. Make sure you seal the bucket tightly.
If you are washing the sensors in a container that doesn't have a lid of its own, you need to find something to secure it. Look for a properly sized kitchen lid or just plug the opening with a piece of plywood or a large book
Step 3. Leave the probes to soak overnight
The fuel is not able to clean them immediately, but it needs at least 8 hours; during the process lift the bucket and move it several times to make sure that every part of the sensors is cleaned.
Step 4. Take out the probes and dry them
After leaving them in the gasoline overnight, you need to retrieve them from the bottom of the bucket or container. Look at how they look - they are much cleaner than the night before. Take a clean cotton cloth and wipe off the fuel residue on the probes until the probes are completely dry.
- To keep your hands from getting fuel, put on a pair of thick rubber gloves as you take the parts out of the bucket;
- You can also use a pair similar to the one you use for washing dishes.
Step 5. Install the probes on the vehicle
Once cleaned and dried, use the wrench to insert them into the exhaust manifold (or manifolds) and into the other seats from which you extracted them; screw them tightening them completely.
- To end the process, use the jack to carefully return the vehicle to the ground;
- Start the engine and check if the "engine light" is still on; it should have gone out. You should also note that cleaning the probes has led to a substantial reduction in consumption.
