I have just been trying out the Live for G15 application in single player, I was messing about in all the cars. I jumped into the FO8 and I found the throttle was acting really strange.
It would cut out like I have run out of fuel, then just cut back in again. It repeats this 3 or 4 times before going back to normal. It only happens on the the "highway" too. As soon as I join the "slip road" it starts, then it ends when I leave the Highway.
I haven't tried it in any other cars.
I also have a replay. Please excuse my driving, my G25 wasn't plugged in so I was using a mouse.