There are a number of symptoms, that can point to your Crankshaft Position Sensor (CKP) failing.
But, can also be confused with the same symptoms, caused by issues with, your Ignition or Fuel Injection System.
So, the speed and position of the crankshaft, are the two key parameters, that the Crankshaft Sensor (CKP) monitors. And, the Engine Control Unit (ECU), uses that information to set parameters, for other operations. For instance, Ignition Timing, Fuel Injection and Variable Valve Timing (VVT).
First, the Crankshaft Position Sensor (CKP), voids the need for manual distributor timing. The Camshaft Sensor (CMP) is used to determine, which cylinder is firing. And, uses that information, to synchronize the fuel injector and coil firing sequence.
But, if you have Crankshaft Sensor (CKP) issues, the Engine Control Unit (ECU) can not synchronize other operations. For example, Fuel Injection, Spark Ignition or Variable Valve Timing (VVT).
Let’s learn about some Crankshaft Sensor (CKP) failure symptoms, so that you can take action, when there’s a problem.
Common Failure Symptoms, For Crankshaft Position Sensors (CKP):
Acceleration Problems
- So, as the engine speeds up, there needs to be adjustments, to the Spark Timing and Fuel Injection. But, without precise input from the (CKP), the (ECU) can not make these adjustments, as well as it should. As a result, this causes poor acceleration and makes your car, fail to maintain a constant speed.
Reduced Gas Mileage
- So, without precise timing information, Fuel Injection will have, wrong (CKP) Sensor readings. As a result, leading to Spark Timing and Fuel Injection errors. As a result, this will affect the fuel efficiency of your engine.
Engine Misfires
- Lack of proper Spark Timing, can cause a different problem. One or more of the cylinders, may Misfire. That is to say, combustion may be disrupted. You will feel, and maybe hear, this as a brief stutter in the engine.
Rough Idling
- You might feel that the engine runs rough or shake at idle. For instance, when you’re sitting at a red light. This is similar to the above, in that it stems from poor Spark Timing. Crankshaft Position Sensor (CKP) failure.
Stalling And Backfiring
- Another sign of a (CKP) failure is, the constant stalling and backfiring of the engine. In such a scenario, the engine, is prone to stalling as you drive. Unlike ignition malfunctions, the car will probably start, even run for a while, only to shut down again. It goes the same, for engine backfiring. If you neglect the warning signs, the engine may get exhausted and die out.
Difficult Starting Or No Starting
- It might be hard to get your engine started, without the fuel it needs or without proper timing. If the (CKP) sensor has failed completely, then the computer won’t send any fuel to the injectors. As a result, leaving you unable to start the car.
Check Engine Light
So, a (CKP) Sensor Failure, may cause the Check Engine Light (CEL) to come on.
As a result, a scan tool could show, any of the following codes:
- P0335 Crankshaft Position Sensor A Circuit Malfunction
- P0336 Crankshaft Position Sensor A Circuit Range/Performance
- P0337 Crankshaft Position Sensor A Circuit Low Input
- P0338 Crankshaft Position Sensor A Circuit High Input
- P0339 Crankshaft Position Sensor A Circuit Intermittent
Testing A Crankshaft Position Sensor (CKP), With A Multimeter:
- Of course, not everyone has access to a scan tool (although they can sometimes be rented from parts stores). A multimeter, is a more common tool. And, a very useful one, for diagnosing many electronic components. A multimeter can measure voltage, current, and resistance. You can remove the (CKP) Sensor, and then test the resistance.
- Attach one end of the multimeter, to each wiring lead of the (CKP) sensor. Resistance of zero means, that there is a short circuit. Infinite resistance means, there is an open circuit. Either one of those readings indicates, that the (CKP) sensor is not working. For any other reading, check it against the manufacturer’s specs. If your reading is not close to the suggested resistance, then you should replace the (CKP) sensor.
Another way to test the (CKP) Sensor is with a multimeter. You do this by checking the output voltage, with the engine cranking.
- You will need an assistant to do this. Be very careful around moving parts as you do this. Probe the wiring connectors and measure the output voltage in AC millivolts. Typically, this reading is around 200 millivolts. But, this can vary, from vehicle to vehicle. So, always check the manufacturer’s specs. If there is no output voltage, then, obviously, your Crankshaft Position Sensor (CKP) is not working.
But, if your test results are within specifications, check the (CKP) sensor electrical connector and wiring harness. Finally, it is common for loose connectors or broken wires, to keep the sensor, from communicating with the computer.
- Also, make sure to check the trigger wheel. The wheel, located on the crankshaft or damper, may have missing or damaged teeth. So, any of these parts, may trigger a (CKP) Sensor or circuit trouble code. These tests will help you determine, the source of your problem. They may help prevent you from making a repair, you don’t have to. If the testing has indeed confirmed, that your (CKP) sensor has failed.
Why Do I No longer Have A Distributor ?
- The advantage of having a (CKP) Sensor is that, you do not need a distributor. The end result is, less moving parts that can break down.
Conclusion
So, if you have a (CKP) Sensor failure, your engine cannot function efficiently, and will eventually fail. A failing engine, is not only costly to repair, but dangerous. So, it is in your best interest, to recognize these symptoms quickly, and get them fixed.
BY DANNY BENDER
