Also, sometimes when I and pulling out of a driveway or have been driving a few feet at slow speeds getting ready to pull into traffic, the car jerks as if the transmission isn't hitting. This only happens at times when I have driven slowly first such as pulling out of my apartments.
I had something similar happen to me, only when the engine was not at opperating temperature and as I was leaving for the first time that day would the car not fully respond when I dove slowly away!
When I say not fully respond, I mean that it was a minor hesitation in the engine that went away in a matter of seconds and did not come back until the car sat overnight!
I thought it was just the way the Zetec was when cold, I'm living in -20c temperatures right now, but after the filter,plugs, and wires were installed the behavior went away!
Unless you have already, I would suggest a tune up!
I hope that this is what you are experiencing and not a trany/engine problem!
Stephen
