Corvette CCM Reverse Engineering Anyone?

[-=Jeff=-]

Setup my bench to read a couple CCMs. but I keep getting the Bus is too Noisy.. I have not changed anything on my setup. Suggestions on what to check?

EDIT:
1990-1991 works but 1992-1993 keeps giving the Bus to Noisy, then is says it cannot find the Heartbeat. I have another port setup and running YAT to read the data, the CCM seems to be sending the commands as expected, but for some odd reason, the Arduino setup to fake the messages is not working. As I thought having the reply messages will help. I also tried driect connection to CCM, (No ECM present)