Parallax Proximity Sensor Problem

Hello, this is my first post though I've been on the forum before. I am programming a moving robot consisting of 3 Parallax Ping sensors. To drive the motors I am using the Sabertooth 2x25. Since this is my first experience building and programming a robot, the other day I blew up the shield on the Arduino board similiar to Proto-Screwshield (Wingshield) R3 Kit for Arduino : ID 196 : $14.95 : Adafruit Industries, Unique & fun DIY electronics and kits by accidentally having the Ground wires from the Parallax Pings touch the wire connected to the motor (darn!). So, i figured out the problem, none of the boards I had been using seemed damaged and I replaced the Arduino shield. I rewired everything completely and correctly. Then when I went to test my program again, 2 of the 3 sensors began reading "0 inches" instead of the correct values. So, then I tried just using the sample Ping code for all 3 sensors without any other code and all the sensor values were perfectly fine and did not read any "0" values. I hadnt changed my original code from before the shield blew up and used the same one. I am stuck on this problem and am confused, if anyone would like me to send them my code I'd be happy to post. Does anyone seem to know a logical place to check so I can solve this problem? Thanks.

Maybe try send your code here and we may figure out or alternatively you can use http://www.societyofrobots.com/robotforum it has very large members community which might answer to your problem