My 2004 Vibe has 265k miles on it! It was still going strong when all of a sudden some weird things started happening. At first it started to 'sputter' I guess as if it was out of gas. Because it is my only vehicle and I currently have to use it to get to work as biking will subtract 1-2 hours of sleep (15 miles, yeah im slow) from my already 5am morning. Well after a few more days of this the 'sputtering' became worse and then it would do odd things like accelerate to 40mph and not beyond with the RPM staying at a solid 2-3k not going above this; this would happen on and off. The other day was the kicked and i'll be borrowing my mother in law's car. The Vibe started to 'buck' and make some really nasty high pitched noise.
Now I know for a fact it isnt an oil problem because I check the oil religiously due to it burning oil because of its high mileage. Also, because of its high mileage, I use 10w-40 not that has anything to do with it just a little more information. I checked the transmission fluid and yeah it is VERY dark I just have a feeling it isnt the transmission. I got it back from the mechanic today and his opinion is the head gasket is leaking and because of this has saturated the serpentine belt with oil. Two of the ignition coils are reporting errors and something else I forget off the top of my head. The quote he gave me was 1300$ but I am hoping to get some opinions/information here and buy a repair manual to try to save some money.\
--edit sort of remember he said something about the cam shaft.