Check Engine Light Car Knock Sensor Low Input - Code P0327 P0332

So you have a check engine light and you scan the vehicle and you find that you have a code P0327 or a P0332. I'm gonna talk about what that means.

Majority of the time when you get that code, that means that these knock sensors are bad, they need to be replaced. On this vehicle, they're located underneath the intake. You have to pull the intake off to access them.

So what is engine knock? So inside your engine, you have air and fuel. And when the spark plug ignites the fuel, there's gonna be an explosion. And that is how your engine is gonna run smoothly. Now, if the spark plug ignites the fuel too early and or the fuel that's in the vehicle isn't the correct fuel, you can get something where there's too much pressure inside the engine, and you're gonna get another ignition over here. It's gonna be like you have a match right here, and you also have a match right here. Now, when you get more ignition over here, that's gonna make any knocking noise. It's going to make a little tapping noise. And that's what those sensors are monitoring.

If you take your meter and you put it on AC voltage and you go to range and you want to go to a millivolts, so we're on millivolts. Now just the leads being out in the air, it's gonna fluctuate. But if you take one of the leads and put it on the sensor, just like that, and then you ground the other lead, just find a good ground somewhere. So if you look at the meter, just like that, and it's at zero, just take a screwdriver and you can just tap right here. And as you tap, you can see that you're getting a reading and that's what a good knock sensor looks like.

So if it wasn't doing anything when you do that, then you'd know it would be a open circuit in the knock sensor itself. You could also check the resistance of the knock sensor itself, and it might be hard to find a spec for this, but if you put the meter on ohms, looks like a little horseshoe, and you put one of the leads on the ground and then put the other lead on the knock sensor itself, we'll get a reading. And because there's two of them in this vehicle, you can compare them and see if they're pretty close, which they are in this vehicle. And these are good. So, if you were doing this same test and you had OL here, that would be a bad sensor. That would be an open circuit. So nothing's working inside the sensor.

Because of the location of these knock sensors being underneath the intake and it not being really easy to get to, it's always a good idea to replace the wiring harness while you're there. This get brittle over time, there's a lot of heat around them and they're not that expensive. So it's a good idea, just replace it. And you may have a condition like this, where you've actually got some corrosion. The old harness was all corroded. Some moisture got in here. There was some water in there, and that's what actually caused the light on this vehicle. So here's the wire connector, that's corroded. And in this situation, you're gonna to want to replace the sensor and the wire because there's too much corrosion. You're not gonna clean that out.

So these knock sensors are really sensitive. So just make sure you don't drop them.

So now you know what to do if you have a knock sensor code, make sure you clear the check engine light and drive the vehicle. You should be good to go. If you enjoyed this video, make sure you subscribe to our channel, ring the bell and turn off all notifications so you don't miss any of our videos.
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