Truck Showing 3 CEL Codes

[powerjokin 6.0]

Check engine light popped up today so I checked it with my CTS and its showing the following:

PO284-Cylinder #8 Contribution Balance

PO300-Random Misfire Detected

PO303-Cylinder 3 Misfire Detected

Also, truck has a bad vibration when the torque converter locks everytime. I was on a 146 mile trip and every time the converter locked around 40-60 MPH the truck starts shaking violently and I have to speed up and shift to 4th. Any idea what this could be?

Do I have to tear the motor apart to fix the codes? Injectors possibly? scorred cylinder walls?

[powerjokin 6.0]

helpppppppp

[powerjokin 6.0]

bummmmmmpppppp

[ajpu1983]

Check compression first.

[powerjokin 6.0]

care to elaborate? compression of the cylinders?

[ajpu1983]

Yeah by running a compression check you can determine if it's a mechanical issue or just an injector failure. You remove the glow plugs, thread in a compression adapter, and crank the engine over until the gauge levels off. Then compare all 8 readings in order to point out a bad cylinder.

[jslewisF250]

I had cylinder #5 misfire and when my truck shifted to OD it bucked and jerked violently. When I mashed down on the accelerator it went away until it shifted back to OD. It was a bad injector! Its been fine since October.

[diablos30]

i would check batteries and ficm voltage first. if they both check out then move on to testing the injectors.

[powerjokin 6.0]

my batteries are a bit weak but they are reading about 12.1 voltz on my gauge. It'll be going into the shop next week to see what the problem is