Land Rover Repair: Low Idle, Alternator, vacuum line, alternator

Question
John,

I recently had my alternator "spruced up" as the dealer puts it.  The battery died.  I recharged it with a generator, then the "check alternator" light came on on the generator.  Assumed it was the alternator.  Had it towed to a repair shop who said the alternator was fine, but should be "spruced up" due to the mileage on the truck.  Since back from the shop, I have noticed a low idle.  What might be the cause? 98 Disco

Answer
I'm not sure what to make of this.  Here in the USA we don't "spruce up" alternators.  We replace them.  The 98 Disco alternator is prone to failure and the only consistent good result I have gooten has been to fit brand new ones.  Rebuilt ones like as not don't work.

I do not know what to say about the low idle beyond looking to see what vacuum line or wire got knocked off or disturbed