i recently had the same symptoms as you. i put a new engine in and a couple of days later it felt as if i put a race cam in the engine. it ran really rough. when you pull the TPS u sen the ecu into a limp home mode and all defaults are ran. I ended up testing everything like pickup coil,coil,tps and they were all good. when i pulled plug wires it ran better HMM running on 2 cyclinders i said. ok then try running a vaccum test to see how "Strong" your engine is running with a new head u should be at middle to high 20's. I did the test an i was only about 15. low vaccuum could be to tight intake valves. i think this is your problem because your head in rebuilt or new. new valves tend to tighten up during the break in. do yourself a favor and check the valves and let us know!! <img src="/forums/images/graemlins/cheers.gif" alt="" />