Random Misfire (P0300) Only in Morning When Cold - JeepForum.com
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post #1 of 1 Old 11-18-2015, 08:39 PM Thread Starter
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1997 ZJ 
Join Date: Nov 2015
Posts: 2
Random Misfire (P0300) Only in Morning When Cold

97 Jeep Grand Cherokee has been misfiring only in the morning when it's cold, under 50 degrees, for about 10 minutes until it reaches operating temperature. I'm at a loss and running out of things to check & replace.

I've taken it to two repair shops and they keep telling me to replace stuff, but nothing has fixed it so far.

Here's what I've replaced:
  • New Plugs, Wires, Cap, Rotor
  • Camshaft Pos. Sensor
  • Cleaned throttle body
  • MAP sensor
  • Intake Air Temp Sensor
  • Idle Air Control Valve
  • Fresh Gas, Fuel Injector Cleaner

Trying to get this fixed before weather gets any colder, not sure the old jeep would like below freezing with this problem. Any help would be great!

Last edited by TRock; 11-21-2015 at 08:17 AM.
TRock is offline  

misfire , p0300

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