69 camaro with an ls1 and t-56, using painless wiring harness no mods except for LT's and no tune. MY car starts fine and idles around 1000 rpms, but as it starts to worm up it starts to lope almost like it's missing. Then the tac starts to go crazy shooting from 1000 to 8000 then back again. Then the resitors on the fuse block start buzzing as the engine dis? What gives I checked my wires and there not shorting out from be cut or anything? I don't have a scanner so i can check for any codes? Thanks in advance.

 

Try disconnecting the MAF and see if the problem goes away is all I can suggest.

 

Could it be an O2 sensor problem?

 

Could be O2 sensors wired wrong......happened to me, the computer sees the mixture going lean on one side so it tries to add fuel, if the signal is coming from the wrong side it will be dumping fuel in the wrong bank of cylinders causing A REAL mess as one side that is lean...gets leaner and the other side gets richer when it's already rich. Then you get this big loping rpm surge as the IAC tries to keep it idling. I finally caught my problem when I pulled the connector off of the right bank and I saw the LEFT bank indicate "open" as the O2 output went to 4.5v and sat there. It also set a code for the left bank. Once I swapped the wires in the harness it was perfect.

 

check for vacuum leaks