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Help with codes PO300, PO302 and PO303

Discussion in 'Wrangler TJ (1996-2006)' started by bob.net, Oct 17, 2016.

  1. Oct 17, 2016 at 2:03 PM
    #1
    bob.net

    bob.net [OP] Member

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    Have codes PO300, PO302, PO303 misfire. Do I need valve springs or new cap wires and plugs?
     
  2. Oct 17, 2016 at 6:52 PM
    #2
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine Moderator

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    Welcome! Can you give more information regarding the engine, and year?
     
  3. Oct 17, 2016 at 9:26 PM
    #3
    C2T

    C2T Well-Known Member

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    2.5" AEV Dual Sport lift, 35" Treadwright Guard Dogs, Black Rock Wheels, AEV Front & Rear Bumpers with Tire Carrier, Fuel Caddy 10 gal. Aux. fuel tank, Warn 9.5ti, 125' synthetic winch line, front axle skid, 20" LED light bar , Bilstein Shocks, steel steering skidplate,
    The p300 may simply be a result of having two other cylinders misfiring so I will ignore that one for now. You need to take a close look at the spark plugs and wires to cylinders 2 & 3. Of course, the whole ignition system is suspect. It does not sound like a coil problem but we cannot rule it out completely just yet. If all else looks good, we may need to check your injectors. Nothing I know of on these codes refer to bad valve springs. I wold think it possible but highly unlikely.
     
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