OBD Guide

P1243

Second Fuel Pump Faulty Or Ground Fault

Severity
🔴 High
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Unstable engine operation under load
  • Loss of power during acceleration
  • Difficulty starting the engine
  • Floating idle speed
  • Check Engine Light Illuminates

Causes

  • Malfunction of the second fuel pump
  • Damage to the pump ground circuit
  • Oxidation of contacts in the fuel pump connectors
  • Problems with the fuel pump relay
  • Open or short circuit in wiring harness

How to Fix

  1. Check the operation of the second fuel pump
  2. Inspect the pump ground circuit for damage.
  3. Check the contacts in the fuel system connectors
  4. Test fuel pump relays and fuses
  5. Diagnose the fuel pump wiring harness

Related codes

Error P1243 by Vehicle Brand