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A more general automotive question not vehicle specific
If a newer vehicle with a dead battery is needing a jump off from another vehicle will increasing the revs on the "jumper" vehicle damage the alternator on the "jumpee" vehicle?
With modern systems I am pretty careful I never have both donor and client engines running at the same time and never connect and disconnect with either engine running. Best practice is to connect up with both engines key off engine off then start the donor and leave it running for a few minutes then go engine off key off and try and try and start the client, if the cient starts run for a few minutes, then key off engine off key off disconnect.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Same as Andy, except I'm ok disconnecting with them both running. My theory is the voltages are going to be close to equal to each other so a spike isn't likely. Just my thoughts.