When your check engine light turns on and a scanner reveals the meaning of code P1374, it means your car's computer has lost track of the engine's precise timing. This matters because your engine relies on exact synchronization between the crankshaft and the camshaft to fire the spark plugs and inject fuel at the right millisecond. Without that synchronization, the vehicle might run poorly, stall unexpectedly, or refuse to start entirely to protect itself from severe internal damage.

What exactly does diagnostic trouble code P1374 mean?

Diagnostic trouble code P1374 specifically points to a problem with the frequency or correlation between the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor. The powertrain control module (PCM) reads electrical signals from both sensors to know exactly where the internal engine components are located during rotation. If the PCM detects an abnormal frequency signal from the crankshaft sensor, or if the signals from the two sensors do not align properly, it stores this code. Figuring out why the P1374 code appears is the first step toward restoring your vehicle's performance and preventing further mechanical issues.

What symptoms will you notice when this code triggers?

You will rarely see this code without feeling a change in how the car drives. Because the computer is struggling to manage ignition timing and fuel delivery, you might experience several noticeable problems:

  • The engine cranks but takes a long time to start, or it does not start at all.
  • Rough idling that feels like the car is shaking or misfiring at stoplights.
  • Sudden stalling when you come to a stop or press the accelerator.
  • Sluggish acceleration and a general lack of power when driving up hills.
  • An illuminated check engine light on the dashboard.

Why did my car's computer set this code?

The computer sets this code when the sensor readings fall outside the expected parameters. Before you start buying replacement parts, it helps to understand the frequent culprits behind engine code P1374. The most common reasons include a failing crankshaft position sensor, a defective camshaft position sensor, or damaged wiring connecting the sensors to the computer. Sometimes, the issue is purely mechanical, such as a stretched timing chain, a jumped timing belt, or a broken reluctor ring on the crankshaft itself.

When you are documenting these sensor readings or printing out repair manuals, keeping your notes readable is highly recommended. If you are designing your own troubleshooting log, using a highly legible typeface like Roboto makes reading the technical data much easier on the eyes.

What common mistakes do people make when diagnosing this issue?

One of the biggest mistakes DIY mechanics make is immediately replacing the crankshaft position sensor without checking the wiring harness first. Rodent damage, chafed wires, or corroded connectors are just as likely to cause communication errors as a bad sensor. Another frequent error is clearing the code and hoping it goes away, rather than actually fixing the underlying timing issue. Ignoring a stretched timing chain will eventually lead to catastrophic engine failure, so skipping the mechanical inspection is a costly gamble.

How do you accurately test and fix the problem?

Fixing the issue requires following a proper diagnostic sequence rather than throwing parts at the car. You need to verify the electrical signals and check the mechanical timing to find the true root cause.

Practical next steps to diagnose code P1374:

  1. Scan for related codes: Use an OBD-II scanner to see if codes for the camshaft sensor are present alongside P1374. Multiple codes often point to a shared wiring issue or a timing chain problem.
  2. Inspect the wiring harness: Trace the wires from the crankshaft and camshaft sensors back to the PCM. Look for melted insulation, broken clips, or oil contamination in the electrical connectors.
  3. Test the sensors with a multimeter: Check the resistance and voltage output of the crankshaft position sensor while an assistant cranks the engine. Compare your readings to the factory service manual specifications.
  4. Verify mechanical timing: If the electrical tests pass, remove the timing cover to inspect the timing chain or belt. Look for excessive slack, worn guides, or timing marks that no longer align properly.
  5. Clear the codes and test drive: Once you repair the wiring, replace the faulty sensor, or adjust the timing, clear the computer memory and drive the car to ensure the check engine light stays off.