Alternator, battery, and now engines dies at cruising speed!
1989 Ford Ranger XLT 4x4 2.9L engine. Engine starts fine and runs fine most of the time. Drove son to school Moday morning about 17 miles on return trip died twice at cruising speed 70 mph on turnpike. All electrical off, oil pressure gauge bottomed, amp meter bottomed, check engine light on, battery light on. Depress clutch, and pop clutch engine truns over and runs as if nothing happened. Drove to shop when they opened they checked it and couldn't get it to do anything.
Background info: This vehicle has 65000 miles and went for 10 years with just being driven 4 to 5 times a year about year ago started driving it more and had to replace alternator and battery. I wrote this one off to not being driven. Alternator lasted about 4 months and started showing over charge of gauge so to it back to shop and they advised it was bad and replaced alternator and battery again that was in Dec. Drove to Kansas in Jan. and alternator quit again. The shop said it must have been overcharging until it burnt out, battery was low on liquid they charged and said it was still good.
I drove direct to shop this morning when I test drove it and it did the same thing once. Picked up mechanic and took him out and of course it didn't do it.
It seems that right before it acts up there is a momentarily sluggish before power shuts off.
Shop thinks it is either Ignition coil or ignition module, but does not know which one. My inlaws who own a shop in Kansas think it could also be battery cables corroded or a short somewhere.
I also forgot to say I checked battery today after return from shop. Battery voltage not running is 13.4v, without any load running is 14.3v, and with headlights on, heater fan on high, radio at loudest is 14.1v.
With the background of alternators it seems that these problems may be interconnected. Could bad cables burn up the alternators, which would damage batteries.
Or would ignition module in anyway affect either of the battery/alternator?
When first started after an incident it seems to idle a little slow and wants to die then something kicks in and idle goes up a little and seems to be normal again.
If any one can help I would appreciate you responses.