The TBI 350 in my 90 Jimmy is running kinda awkward. After I had it tuned up, it started running rough. When just plain riding around, it's fine. When I start it in the morning, or any time that the engine is cold, it runs like a 3-legged dog. It skips and is just plain rough, but if you rev it up one time, it runs fine. Also, when it's hot and when you're barely on the throttle, it starts sounding like it's got a big cam in it, kinda like it's loading up the cylinders before it fires. What is you take on this?