Narrative:

Cruising at 13000 ft in IMC; eastbound; in light rain; began to pick up ice; advised by center that the WX conditions would be improving in route of flight; should be coming out of bad WX. At 5 mi from ZZZ; I requested diversion to ZZZ; at 2 mi from ZZZ engine began running rough; switched to alternate air; difficult to hold altitude; approved to ZZZ airport; marginal radio contact with center at lower altitude; another aircraft relayed some communications; within 1 mi of airport visually; landed runway 4 at ZZZ; called FSS on the ground and requested they contact center to cancel IFR flight plan. Flight plan cancellation confirmed.

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Original NASA ASRS Text

Title: PA28 PLT ENROUTE AT 13000 FT IN IMC DIVERTS DUE TO A ROUGH RUNNING ENGINE AND DIFFICULTY HOLDING ALT.

Narrative: CRUISING AT 13000 FT IN IMC; EBOUND; IN LIGHT RAIN; BEGAN TO PICK UP ICE; ADVISED BY CTR THAT THE WX CONDITIONS WOULD BE IMPROVING IN RTE OF FLT; SHOULD BE COMING OUT OF BAD WX. AT 5 MI FROM ZZZ; I REQUESTED DIVERSION TO ZZZ; AT 2 MI FROM ZZZ ENG BEGAN RUNNING ROUGH; SWITCHED TO ALTERNATE AIR; DIFFICULT TO HOLD ALT; APPROVED TO ZZZ ARPT; MARGINAL RADIO CONTACT WITH CTR AT LOWER ALT; ANOTHER ACFT RELAYED SOME COMS; WITHIN 1 MI OF ARPT VISUALLY; LANDED RWY 4 AT ZZZ; CALLED FSS ON THE GND AND REQUESTED THEY CONTACT CTR TO CANCEL IFR FLT PLAN. FLT PLAN CANCELLATION CONFIRMED.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.