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1998 JEEP CHEROKEE

4.0L I6AWDAUTOMATICgas
11 active safety recalls on this vehicle — view recalls
Repairs0Labor505Torque2487Fluid9DTC645Battery0Maintenance0Recalls11
P0301high severityPowertrain

Cylinder 1 Misfire Detected

on 1998 Jeep Cherokee 4.0L I6 · AWD

What this code means

The PCM has detected a misfire condition specifically in cylinder 1.

Symptoms

  • Check Engine Light
  • Rough idle
  • Vibration
  • Loss of power
  • Fuel smell from exhaust
  • Poor fuel economy

Common causes

  • Worn or fouled spark plug #1
  • Faulty ignition coil #1
  • Damaged spark plug wire
  • Faulty fuel injector #1
  • Low compression cylinder 1
  • Vacuum leak near cylinder 1

Diagnostic steps

  1. Swap ignition coil #1 with another cylinder to see if misfire follows
  2. Inspect spark plug #1
  3. Test fuel injector #1
  4. Check compression cylinder 1
  5. Check for vacuum leaks near cylinder 1

Repair notes

Try swapping coil first. If misfire follows the coil, replace it. If not, check plug, injector, then compression.

Other Powertrain codes on this vehicle

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