Question about 1999 Jeep Grand Cherokee

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1999 jeep grand cherokee cylinder misfires/malfunctioning

I pulled the codes off my 99 Jeep Grand Cherokee and got P0303, P0304 and P0306. I believe it is those three cylinders. Now i know that means they are malfunctioning or misfiring but how do i go about fixing them myself instead of taking it into the shop. I cannot drive it right now because it is making such a horrible knocking sound. Its very loud and obnoxious and i am afraid its gonna blow up or something. please help me out on this one i really need to get it fixed asap!
thank you
~Ashley~

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I guess the best place to start is change plugs and wires. A timing light would come in real handy. You could check to see if you had spark on all cyllinders before you start blowing cash. If you have spark in the wires, then change plugs. If theres no spark in the wires, then the problem is before that. Like coil, or idle control sensor etc. Keep me posted and i'll try and help as much as possible. Not much a keyboard can do.

Posted on May 15, 2009

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Posted on Jan 02, 2017

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