I have been having a similar issue with my Compass. I am the second owner, but I bought it from a reputable dealership. It had 8,000 miles on it when I purchased it at the beginning of this year, and now has slightly less than 12,000. It ran fine for the first few months, but for the past two weeks or so it has been intermittently starting (or stalling immediately after it starts). It will crank, but won't turn over (so it's not
a clicking sound like the battery is dead, but rather like it's trying to start, but isn't catching). It's intermittent, so I could try to start it in the morning 4 times, and it will catch on the 5th, or it may start right away. It also started to stall out if I'm going slow (through a parking lot, or leaving my driveway - again, totally intermittent!)
When I took it in to the dealership last week, they replaced the Throttle Body, and did two computer updates. It seemed ok for maybe a day before it started back with the intermittent start and now stalling after starting (in the past week it's stalled maybe 5 times after starting or while at a light - but I've found that if I rev the engine while idling it is less likely to stall. It also seems less likely to stall if the AC is off).
It's obviously still covered by factory warranty, but if they weren't able to find/fix the root of the problem last time, I'm wondering if they will be able to fix this before the factory warranty runs out in a few months. Is it true that if you brought it in with an issue covered under factory, if the issue is not resolved, they still have to cover it under factory even after the warranty has expired?