Okay so been chasing multitude of problems lately in the van. at this poit have replaced entire fuel system, pump, lines, sending unit, etc. have done timing few times now. (pretty convinced that the thing jumped timing which started the downward spirial) within the last 3-4 weeks and has been throwing me for a loop. Can set timing, crank timing at 0 degrees on bell housing, camshaft sprocket arrows parallel with cam cap parting lines, dizzy slot parallel with block. great, so start it up and let it warm up to operating temperature. no problem, but once you pull the coolant temp sensor, it will hardly stay running, and if it does not stall, its pretty much not possible to set base timing to 12 degrees since its bucking/choking so much. have gone all over all vacuum lines, which is only 3 in total. This setup is a ported swirl head, +40s, walrbo 255, two piece intake, TU log manifold, TU 3" sv and 3" full exhaust and a tranny buster 50 trim t3/t4 hybrid. TRULY do not know what am missing at this point, it was fine earlier this summer. Thought maybe engine was hurt but has 125 psi on all 4 cylinders, and doesn't smoke or burn any oil at all. WOT its in the 12s for AFR, earlier this year was mid 11s or so. Starting to wonder about integrity of the computer itself, if its starting to fail.. Also only codes I have are 33 and 34, which are both irrelevant. Have swapped known good coils, wires, cap, rotor, HEP pickup, etc. Even tried a new wideband sensor to rule that out, since the one was about ten years old. Anyone else ever have an issue with setting base timing? and in MP tune, which section controls the base timing tables? Thanks guys for any input. Trying to get this wrapped up before it gets real cold out.