P0379 — Timing Reference High Resolution Signal B Intermittent/Erratic Pulses
Drive with caution — fix soon.
What P0379 means
This code sets when the 'B' high-resolution timing reference sensor sends an erratic or intermittent signal instead of a steady stream of pulses. It's commonly caused by a loose or corroded connector, chafed wiring, or a sensor that's starting to fail. Because the fault comes and goes, it can take a careful inspection of wiring and connectors to pin down, but it's usually repairable without engine teardown.
Common symptoms
- Check engine light is on, sometimes flickering
- Engine surges or hesitates intermittently
- Random stalling that comes and goes
- Hard starting at times
- Brief rough idle or stumbling
Common causes
- Loose or corroded sensor connector
- Chafed, broken, or intermittent wiring
- Failing crankshaft or camshaft position sensor (B)
- Damaged or contaminated reluctor ring
- Electrical interference or poor ground
Typical repair cost
$150 – $500
Varies by vehicle and root cause.
Frequently asked questions
Can I keep driving with a P0379 code?
Usually yes for short trips, but the intermittent nature means it could stall unexpectedly. Avoid long drives and get it diagnosed soon so you don't get stranded.
How much does it cost to fix a P0379 code?
Expect around $150 to $500. Wiring and connector repairs are often cheaper, but intermittent faults can take extra diagnostic time, which adds to labor.
Is a P0379 code serious?
It's moderately serious because the on-and-off signal can cause sudden stalling. It rarely damages the engine, but it's worth fixing promptly for safety and reliability.
Why is a P0379 code so hard to diagnose?
Because the fault is intermittent, it may not show up when the technician checks. Loose connectors and chafed wires that only act up with heat or vibration are common culprits.