Hi! I have a 2007 Kia Rio LS.
I can’t get it to do this ALL time time, but when I accelerate hard (passing, getting off the line quickly) I hear a metallic sort of coughing sound from my car. It seems to happen around 30-40 MPH, but not the same speed each time. I think I may have heard that sound once while it was idling.
I have done all the scheduled maintenance (I’m behind a bit for the 70,000) that my mechanic has recommended, and I keep up OK with my oil changes. We’ve skipped doing the timing belt thing, because it’s a tear apart job- we’re going to wait until ‘other things’ need doing and get it all in one fell swoop. This is my road trip car, and Wednesday I’ll be going from central Texas to Northern Illinois, and driving back a week later. I’m worried my transmission is slipping, or my timing belt is prepping to do something horrible while I’m on the road. Probably in the middle of nowhere…