Surging when going into drive

Hey people, I have this problem when I put my truck into drive it surges foward from 600 RPM at idle to about 1000+ RPM when going into drive and you feel the truck lurch foward. I really notice it when the A/C is on it is hard to slow the truck down. I have a 98 Silverado 5.7 Z71.:screwy:

Would need more diagnosis, but from your description sounds like trans. GM goodwrench rebuilts are very reasonably priced.

Here's another, stronger possibility -IF- this particular engine uses the MAP instead of MAF on the injection -

Press and hold in the brake without shifting the transmission. If it does it then, suspect a bad brake booster and replace the booster. What would cause this is a vacuum leak - the MAP sensor detects a loss of vacuum while the oxygen sensors detect a leaned out mixture, and the PCM suspects the driver might be applying some throttle and delivers some extra fuel to the injectors to compensate for the leaned out mixture.

Thanks for the reply, but when I put my foot on the brake before I shift there is no problem it is just when it goes into drive it ramps up. But you bring the point of it running lean would a 130 deg stat make it do this because it thinks its cold? The other day I on my way to work I was doing about 85 to 90 mph and after that when I drove home it was fine.