This is pure guesswork on my part.
Sounds like an intermittent problem and it is likely the alternator. I assume they replaced the battery.
If the smell is "electrical" as opposed to "rubber", I would go ahead and have the shop you trust change the alternator and check all the mounting bolts for alignment. And ask them to check the wire harness to the battery. Inspect the serpentine belt for excessive wear and/or burning and replace if needed.
Hopefully that is it. Avoid the dealer unless you want to pay $600-700 for this service with a new OEM unit. Should be able to locate an aftermarket or rebuilt unit for less.
Sounds like an intermittent problem and it is likely the alternator. I assume they replaced the battery.
If the smell is "electrical" as opposed to "rubber", I would go ahead and have the shop you trust change the alternator and check all the mounting bolts for alignment. And ask them to check the wire harness to the battery. Inspect the serpentine belt for excessive wear and/or burning and replace if needed.
Hopefully that is it. Avoid the dealer unless you want to pay $600-700 for this service with a new OEM unit. Should be able to locate an aftermarket or rebuilt unit for less.