I don't know about the ecu or the tps, but my speedo gauge did the exact same thing. When you drive does the trip counter increase? If so the vss is fine and the gauge itself is dead(happened to me). If the trip counter does not increase I would learn towards the vss.

First check to make sure the vss is still plugged in.

Okay got some good theories but I do know what I did wrong for sure. so maybe someone can say yeah thats why you got a burned ground fuse. Front o2 never worked also I soldered the gm map bar sensor wrong. So I replaced the front o2 resoldered the the gm map bar sensor. Vss is plugged in will report about the trip on the odometer this weekend. Also I got three codes before finding the burned ground fuse p0100 p0110 p0115. Which is volume air flow circuit malfunction intake air temp malfunction and coolant temp malfuntion. So i'll replace the coolant temp sensor but I just bought that mas off ebay should I buy another one just to be safe. Thanks a lot appreciate the help

Well I'm done finaly got the car perfect, tuned and runs great. It was definetly worth it. Basically it was a lot of things that went wrong. Okay The generator relay caused a short to ground that fried my ecu. Also I put a 3000 gt throttle body on my car. The problem was that no one could tell me how to set it. Thats why my tps came unplugged .
Anyway cut two notches in the tps where the bolts go in and then just bring it to oem specifications for a 2g. Problem was you couldn't rotate it enough to get it in specifications. Thats why you cut the notches in it. Really easy fix. The vss did just come unplugged and the o2 never worked.
Thanks everyone my cars been down since july 2009 and I can't ever thank dsm tuners or midsm enough. Dont give up it's so worth it are cars are so fast when built right. Trust me there a tank. Take your time do it once and do it right.

My car did that temp sensor circuit thing before. I wan't happy. I'm glad that is wasn't an eprom ecu and my buddy had one at his house he was willing to let go for cheap.
Glad you found out the problem. These cars are too fun to drive. Mine was down for a whole year just waitning on me to finish the engine.