So, I just got the fuel pump replaced in my Renegade, (-$490), there was an issue when he tried to start it up again after he replaced it so he had to run a new ground to bypass the sentry key module (something I've posted about having issues with several times over the years, code NO SKIM BUS). Since then the Jeep has been very sluggish when starting, like it had a dead or dying battery (I figured that's what it was since it was quite old). Took it to Advance, they tested it, turned out the battery was bad. Bought a new battery (-$120), made no difference. Still sluggish starting up, had to try starting it twice before it actually caught. It runs fine and drives fine, no issues once it's running.
Had a couple come to take it out for a test drive last night (it's for sale at this point because it's too expensive to own two cars) and OF COURSE, as soon as they rev it up, it throws out something completely new: flickering lights, odometer shutting on and off, etc.
Today I went out, started her up, revved it a bit, lights flickered a little but nothing like yesterday. Turned it off, and wouldn't turn back on. Now it's so dead even the remote can't get the doors locked.
Long story short, I'm thinking alternator, which is a fairly easy swap I can do myself. My questions are a) do you think it is the alternator and b) if it is, how do I know which specific alternator to buy? I'm shooting for an OEM but there are several different versions (136 amp, etc.) Is it possible something got screwed up when my mechanic put the new ground in? It was fine before he touched it! He's always been good and fair, and people speak very highly of him so I'm hoping it's not his fault, but who knows?
Thoughts?