Hey just a few quick questions. After swapping in my 350 from a tired 305. The engine has a backfire hesitation and likes to be advanced to about 10to12 degree's with the computer plug un hooked. Then once its hooked back up it runs decent but has lean pop through the intake. If its timed at zero it runs bad. I have swapped the injectors/ chip and an afpr. It has a small rv cam and headers with an intake etc. MSD ignition and wires. I think its a lean condition but have to wait for my Guage to come in. Im getting a code 42 wich is ecm or ignition module. Im just wondering if its possible that the computer is causing this problem and I need to replace it? I know that it needs tuning but it should run respectably with the mild cam that I have. Any suggestions on what to check for. Ignition module or computer??? I have to run it advanced to make it at least drivable!! Will the computer still run an engine if it is having problems??? I always thought that if an ignition module fails or is having problems that it will not run at all??? Any thoughts would be greatly appreciated!!!!!! Im on a limited budget and still waiting for my tuning gear to set everyting strait. THANKS