340 Engine Shake

plumkrazee70 said

It's a speed hut electric. I thought that also, but all the Guages are daisy chained together with their harness. They get one power and one ground and I'm. It experiencing any other Guages fluctuate like that. (I would think if it's a voltage issue, I would see it elsewhere) I'm getting 14v at idle. I was wondering if something could be a wrong with the oil pump drive or dist. shaft?

Click to expand...

I'd rule out a sensor issue, but that would be the concern - an issue with the pump/distributor drive.

I suspect it's actually an intermittent ground issue. I ran a spare battery ground cable from where my main ground connects at the head to one of the flange bolts on my Fitech. No idea if it did anything, but figured a good ground couldn't hurt.

I'd add battery volts to your 'large gauges' and see if it fluctuates at all at idle, or in time with the shake. I highly doubt the pressure is actually fluctuating, but adding a T and running a mech gauge is a good idea.