Cyl 3 compression is low. Engine must run rough.
The cause may be carbon deposits on valves or piston rings.
I had the same low compression problems with CYl 1. Engine was shaking on idle and low RPMs, smoother at high RPMs. Seafoam, STP additives ect. did not help. A few reputable shops could not solve the problem, recommended engine swap, about $4k. Damn.
On assumption valves or piston rings were leaky due to carbon deposits, I used GUNK Motor Medic engine flush $4 at Walmart:
https://www.walmart.com/ip/Motor-MedicUsed half strength, half bottle, idled engine 15 minutes. Dumped oil was black and sludgy. Repeat another engine flush and compression was even on all cylinder, engine smooth like new. I routinely cruise at high speed and long trip. Engine smooth and strong after 320K miles.