P0728 moderate

Engine Speed Input Circuit Intermittent

The P0728 code means the vehicle's onboard diagnostic system has detected: Engine Speed Input Circuit Intermittent. This is a moderate severity code.

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Keep driving?
Short distances only
DIY difficulty
hard
Estimated cost
$100 - $350 (parts and labor)
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Common Symptoms

  • Check Engine Light illuminated intermittently
  • Random engine stalling
  • Occasional harsh shifting
  • Sporadic tachometer fluctuations

Probable Causes (Ranked by Likelihood)

  • Loose CKP sensor connector Very High
  • Intermittent break in CKP sensor wiring High
  • CKP sensor air gap changing with vibration Moderate
  • Failing CKP sensor Moderate

Frequently Asked Questions

Can I drive with code P0728?

Drive short distances only. Engine Speed Input Circuit Intermittent can cause unsafe or unpredictable transmission behavior.

What causes P0728?

The most common cause is a faulty sensor or wiring issue. Loose CKP sensor connector is the most likely cause.

Is P0728 expensive to fix?

Estimated repair costs range from $100 - $350 (parts and labor). Sensor replacement is the most common fix.

Mechanics Guide Step-by-step diagnosis

Step-by-Step Diagnostic Procedure

  1. Wiggle CKP sensor connector while monitoring RPM on a scan tool

  2. Check CKP sensor mounting bolt for tightness

  3. Inspect wiring for damage at stress points

  4. Monitor RPM signal during driving for dropouts

  5. Replace CKP sensor if intermittent signal continues

Sources 1

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)

Commonly Affected Vehicles

  • 2003-2015 Toyota Camry
  • 2004-2016 Honda Civic
  • 2005-2017 Ford Fusion
  • 2002-2014 Nissan Sentra

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