I have a 91 Mr2 auto N/A. I bought it very cheap but it has a issue I just cant seem to solve. The car starts up but right from the startup runs very rich and rough idle, engine shaking to the point sometimes that my mirrors vibrate. The car has no power, I have to floor it just to get it around my driveway. The rough idle seems to get better when the rpms are higher, and on warmer days I notice a huge improvement, where it will hold an idle better without stalling or getting close to that point. So far I have replaced spark plugs with ngk's (checked them and they are black from rich), brand new ngk wires, checked compression on all 4 cyllinders which is good, timing is good, oil is good along with all other fluids, brand new distributor cap and rotor, replaced actual distributor, replaced ignition coil and ignitor, replaced ECU, confirmed fuel pump working by shorting terminals, replaced EGR VSV, tested EGR seems fine along with EGR Modulator, looked for vacuum leaks cant seem to find any, removed intake, brand new O2 sensor and tested with multimeter to confirm working correctly. Also, when revved to 2000-2500rpm the engine revs bounce up and downand speedo guage does same. I cant get a CEL code by shorting terminals, and the check engine light will go on and then turn off. Anyone else had this issue, i am now completely stumped on where to go next.