In the first post, you just said Camaro. What year? Are we talking 60-80's camaro that has a carburetor or is it something newer with OBDI or OBDII software on board? If there is a vacuum leak or something (which would cause a horrible idle), it would show up on the computer. I'd say still go ahead and check every connector end on the big 3 you did, something isn't terminating properly or has a bad connection/grounding out.