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p0300, rough idle, breaks up under boost..

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Old Oct 22, 2014 | 11:17 AM
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Default p0300, rough idle, breaks up under boost..

hey there, the truck is a 02 2500 with lq4. on3 76mm turbo, log manifold, 60mm wg, 50mm bov, 3" IC and piping, electric fan, 60lb injectors, aero 340 pump. The three issues the truck is having is it throws a random misfire code p0300 and the truck started idleing rough and breaking up under boost. what are some things i should check? thanks in advance for all the help!
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Old Oct 22, 2014 | 11:24 AM
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Check your fuel and spark, start unplugging injectors and coil packs one at a time, maybe you have a dead one. When you unplug a good one the engine should run worse but if you unplug a bad one there shouldnt be any changes. Or get a infrared thermometer and see if any cylinders are colder than others
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Old Oct 22, 2014 | 12:18 PM
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Check your plugs and wires too.
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Old Oct 22, 2014 | 12:38 PM
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Its either sparkplugs or wires. I would bet you have a burned plug wire.
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Old Oct 22, 2014 | 12:58 PM
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yup, not to many places to look. just like every one said; check the gap on your plugs, make sure theyre not dark in colour.
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Old Oct 23, 2014 | 10:09 AM
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alright ill start with plugs and wires, they could stand to be replaced any way. What is a good plug and gap to run as well as which wires are good to run?
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Old Oct 23, 2014 | 01:30 PM
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I had some really nice wires on my truck and recently had one burn up. I went to take the rest off for inspection and 2 others the wire pulled out of the connector in the boot.

I now have the ACDelco short wires back on and that's all Im going to use from here on out. Just make sure you have them protected from the heat with some wire protectors.
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Old Oct 25, 2014 | 09:50 AM
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Just like everyone else said, check your plugs...
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Old Dec 12, 2014 | 08:54 AM
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what plug and gap should i run?
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Old Dec 12, 2014 | 11:07 PM
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I have a gauge for that
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br7ef at 0.025"
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