Seeing a P1374 trouble code on your scanner means the engine control module is losing track of engine timing or struggling with the ignition circuit. This matters because without accurate timing data from the crankshaft position sensor, the computer cannot inject fuel or spark the plugs at the right moment. You will likely experience rough idling, sudden stalling, or a complete failure to start. Finding the exact P1374 code causes quickly prevents further damage to your catalytic converter from unburned fuel.

Before grabbing new parts, it helps to get a clear picture of what is failing. You can find a complete understanding of the vehicle code P1374 meaning by looking at how your specific manufacturer defines it, as General Motors and Ford sometimes use this code for slightly different sensor circuits.

What components actually fail to cause a P1374?

Most of the time, this code points directly to the crankshaft position sensor or the ignition coil control circuit. The sensor reads the teeth on the reluctor wheel attached to the crankshaft. If the signal drops out, the engine computer gets confused. A detailed code P1374 explanation shows that the issue usually boils down to electrical interruptions rather than massive mechanical failures.

Here are the most frequent hardware failures that trigger the check engine light:

• A faulty crankshaft position sensor that has degraded from constant engine heat.
• Frayed or broken wires in the sensor harness, often caused by vibration rubbing against the engine block.
• Corrosion on the electrical connector pins where moisture has seeped in.
• A damaged reluctor wheel with missing teeth, which sends a scrambled signal to the computer.
• A failing ignition coil that is shorting out the primary circuit.

How can you tell if it is the wiring or the sensor?

Guessing leads to wasted money. Many drivers buy a new sensor only to find the code returns a week later. To isolate the true problem, you need a digital multimeter. Check the wiring harness for continuity and look for a steady 5-volt reference signal. Some mechanics prefer printing wiring diagrams using a clean, highly legible typeface like Open Sans to avoid eye strain under dim garage lighting.

If the wiring tests perfectly and the voltage is stable, the sensor itself is likely dead. Engine heat eventually bakes the internal magnets and copper windings, causing them to fail. According to NHTSA equipment guidelines, intermittent stalling linked to sensor failure should be addressed immediately to avoid highway safety risks.

What are the most common diagnostic mistakes?

Skipping the visual inspection is the biggest error. Before testing electrical resistance, look at the connector. Oil leaks from a nearby valve cover gasket can wick down the wiring harness and ruin the sensor connector. If you ignore the oil leak, your new sensor will fail just as fast.

Another frequent mistake is ignoring the reluctor wheel. If you clear the code and it comes back immediately while the engine is cranking, the physical tone ring might be cracked or clogged with metallic debris. Understanding these specific P1374 code causes saves hours of frustrating trial and error.

Steps to fix the issue permanently

Follow this sequence to resolve the problem without throwing unnecessary parts at the engine:

1. Scan the vehicle and record all pending and stored codes. Clear them and drive to see if P1374 returns.
2. Visually inspect the crankshaft position sensor wiring for chafing, burns, or oil contamination.
3. Unplug the sensor and test the connector for a 5-volt reference, a solid ground, and a clean signal wire.
4. Measure the resistance of the sensor itself using a multimeter and compare it to the factory specifications.
5. Use an oscilloscope to check the reluctor wheel pattern while cranking the engine. A missing peak indicates a physical gear issue.
6. Replace the faulty component, clear the memory, and perform a relearn procedure if required by your vehicle model.