I was on my way back from San Francisco yesterday via United Airlines when about an hour outside of Toronto we were advised that we had an engine problem. Since I am writing this post, you know I’m okay 
At about 14:30 PST the captain came on to advise us that we would need to land shortly in Chicago as we had a problem with one of the engines, it was not serious but could become serious and therefore we could not continue on to Toronto. During the flight we experienced some quite rough turbulence however it was really short so not a big deal. Otherwise the flight seemed to be pretty fine.
We landed safely at just before 15:00 in Chicago with a strange bump on the runway and a quick power flutter on board but otherwise pretty uneventful. Of course as standard procedure likely requires the runway was surrounded by fire trucks and emergency vehicles. Thankfully they were not required.
Once on the ground we deplaned and were told that the gate next to us was a plane which we were going to board and continue on to Toronto. We boarded within a half hour and were on our way again. Once on board we were told that there was an indicator light which indicated that there was imminent failure of the engine as a result of vibration which the pilot said was odd since there was no vibration. It was believed that it was simply a sensor malfunction.
In total we landed in Toronto about an hour and a half to two hours later than planned. All in all pretty well handled.
My question is, as a courtesy to passengers does United not offer some sort of “we’re sorry you had to be diverted to Chicago with an emergency landing due to imminent engine failure…” please give us another fly sometime….?
Happy Travels…
Patricia
