Try r/CarAV instead. You generally don’t have mechanics install remote start systems and alarms.

Check the help section at your local chain auto parts store.

You need some kind of clutch. Generally a centrifugal clutch will engage off idle to the shaft driving whatever you are driving, unless it’s a pump, and that’s usually self regulating.

As long as it’s 98 (or a 96 V8 Ford) and newer, any OBD II scanner should be able to read and erase codes. I think you can find one under forty dollars at Harbor Freight Tools.

Send it back and get one with a cage or you’ll soon regret it. I’ve been told they become out of balance and warp easily and you will have noise and shorter motor life span.

Check your motor and transmission mounts as well as your universal joints for the clunk.

First off all, never go to AAMCO. Check the codes and get back to us.

I would call the shop and let them know you are no longer invested in the vehicle and offer to sign over the title in lieu of payment. This will save them the trouble of placing a lien on the title and possibly suing you.

Your other, more responsible option is to pay the man and sell it yourself. That will save you the trouble of having a lien on your credit report and getting sued for what they couldn’t recoup from the sale of your car to the scrap yard for the price of scrap metal.