Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Time Pressure
Aircraft Equipment Problem Critical; Deviation - Track / Heading All Types; Inflight Event / Encounter Weather / Turbulence
Flight Crew Landed in Emergency Condition
Aircraft; Weather
I was on the RNAV XX approach into ZZZ. At ZZZZZ; I did my in-range flow and reduced power to 21 inches of manifold power; turned the aux pumps to low; and went through the rest of the flow. Shortly after that I started to notice vibration; though initially; I wasn't sure whether it was vibration or just a continuance of the moderate to severe turbulence we had experienced over the mountains. Then I saw that the fuel flow on the right engine had gone up to about 150 while the left engine was at around 100. Also the rpm and manifold pressure indications on the two engines had diverged. I also saw that I wasn't holding speed at this power setting even though I was descending; so I pushed both throttles up to maintain 120 knots. I wasn't sure which engine was the problem initially - we are trained to look for deficient fuel flow and by that measure the right engine seemed to be working overtime while the left engine was deficient. I then noticed that I had drifted right of course. That indication; along with the fact that the left engine rpm; manifold pressure and fuel flow seemed to be normal; suggested that the right engine was the problem; though it still seemed to be making some power. I corrected the course deviation; got back on course; maintained speed; delayed deploying full flaps until I was absolutely sure that I had the runway made and then landed. Once I pulled the power back to idle and landed; the right engine quit completely. I taxied to the gate on one engine. I was confident that it was safe to do so as the pavement was completely dry and there was no ice.
C402C Captain reported vibration and engine failure on approach.