Q: Van shakes, makes knocking noise - 1993 GMC G2500

asked by on September 13, 2016

The problem with my van occurred out of the blue. I was driving the other day and was stopped in the traffic at one point. When I started accelerating to keep driving, the van shook badly. Then it ran very rough. The rest of the drive, the van kept shuddering and there was a knocking noise. The shuddering was the worst both during acceleration and deceleration. What might be the cause? What parts do I need to replace?

Hello. You will need to find out if your engine is misfiring due to an ignition part like plug wires, plugs, or distributor parts like a cap and rotor or the module. If all the tune-up maintenance is done to replace all the above parts, then it should run good. You may just have a bad cap and rotor, but the wires and plugs could be causing them to burn out. To have this checked, enlist the help of a certified technician from YourMechanic to diagnose the vibration issue and guide through repairs.

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