Question

2009 JEEP COMPASS 2.4L
- P0301 CYLINDER ONE MISFIRE
- IGNITION COIL ONE REPLACED WITH NEW ONE
- CODE CLEARED
- CODE AND PROBLEM CAME BACK SIX DAYS LATER
- SPARK PLUGS ONE AND TWO SWITCHED
- CODE AND PROBLEM CAME BACK A FEW HOURS LATER
- CODE CLEARED AGAIN
- PROBLEM COMES BACK GENERALLY ON A COLD START AFTER SITTING FOR A WHILE
- RUNS NICELY WHEN NO CODE THOUGH

Answer 1

Hi there,

Do a pressure test on the cooling system for one hour, then pull #1 plug and check for coolant on top of the piston. You may have a small head gasket leak that is allowing the coolant into the cylinder. Then when you first start it after sitting a long time the coolant own't burn and you will get a code for the misfire. Once the coolant is pushed through, then the engine runs fine.