Found one towards the front of engine block on passenger side that heads up to alternator and body ground.
Is there also a larger one somewhere on the rear of the engine/transmission, and if so, where is it?
Having funny electrical issues at about 140K miles, all tend to be worse when driving in heavy water or slushy roads.
Moisture problems are classic ground sympthoms. On the XJ/MJ/YJ there is a braided strap between the rear of the head and the firewall on the drivers side. That was Mike Romain's favorite for rotting out. I also have a bundle of grounds from the heater controls and fan to a stud just above and behind the oil filter on the passenger side. I've also seen straps around the motor mounts between the engine and the frame.
The only one on the 93ZJ is off of the ignition coil bolt, passenger side same for the 93-95 and that's what you found. Best way to test engine ground is using a jumper to connect the block to the chassis ground, then to the battery ground.
If the engine smooths out at the battery and not the body then you have a bad battery cable as well.
I remove it, burnish with 80 grit or a wire brush, reconnect, then smear on some dilectric grease to keep the rustbunnies away.
Its not engine roughness, and I never use a brush when a Dremel will do.
Its the damn speedometer. In wet weather it gets twitchy and even stops functioning for a while. Wont stick around long enough to see if cruise control works when speedo don't--as that would eliminate the cheaper stuff. If the electronic module in the dash, just may keep the GPS in the jeep.
If you have the electronic speedometer, pull the sending unit plug on the transmission and clean all the terminals with tv tuner cleaner or something similar, pack the boot with silicone grease, then re-install.
It appears moisture is getting under the boot. If the boot is bad, see about a new one or after installation, coat with RTV.
Budd
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