Timing Reference High Resolution Signal A Too Many Pulses
The P0370 code means the vehicle's onboard diagnostic system has detected: Timing Reference High Resolution Signal A Too Many Pulses. This is a critical severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- hard
- Estimated cost
- $100 - $600 (parts and labor)
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What Are the Symptoms of P0370?
- Check Engine Light on
- Erratic engine operation
- Engine stalls unexpectedly
- RPM gauge jumps erratically
What Causes P0370? (Most Likely First)
- Electromagnetic interference on crank sensor circuit Very High
- Damaged reluctor wheel with debris causing extra pulses High
- Faulty crankshaft position sensor Moderate
- Loose crank sensor allowing vibration-induced false signals Low
Can I Still Drive with P0370?
No — stop driving. P0370 is rated critical severity. Continuing to drive in this state risks further damage — get it looked at before your next trip.
Frequently Asked Questions
What causes too many pulses?
Extra pulses usually come from metallic debris on the reluctor wheel, a loose sensor vibrating, or electrical interference on the sensor wiring.
Can metal shavings cause P0370?
Yes, metal particles from engine wear can stick to the magnetic reluctor wheel teeth, creating extra signal pulses.
How do I check the reluctor wheel?
On some engines you can inspect it by removing the crank sensor and looking through the hole with a flashlight and inspection mirror.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0370?
-
Check crank sensor mounting bolts for tightness.
-
Inspect reluctor wheel for metallic debris stuck to the teeth.
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Check sensor wiring for routing near high-current wires that could cause EMI.
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View crank sensor waveform with oscilloscope. Look for extra pulses or noise.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Which Vehicles Commonly Get P0370?
- 2010-2020 Chevrolet Cruze (1.4T)
- 2012-2019 Ford Focus (2.0L)
- 2008-2018 Honda Civic (2.0L)
- 2011-2020 Toyota Corolla (1.8L)
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