I have a 1993 civic dx 4d 1.5L. The problem im having is I am unable to get the idle set where I want it. On cold start engine revs to 1500-1600 rpm till it reaches proper temp, and slowly idles down. During driving or while idle o can brake and the engine will surge a sec anywhere from a couple hundred rpm and then return to its idle. It also does it sometimes by itself. After this occurs I can tap the gas pedal in small amounts repatisously till the engine kinda ckokes it sounds like. This will in my opinion be the reason why my 3rd gear grinds a little during the shift from 2 to 3, because the engine surges enough to cause this issue. If I brake while sitting it will raise my idle a few hundred rpm. When the coolings fans kick on this will happen, and after the fans turn off. Same goes for turning on my head lights. It has new spark plugs, rotor cap, water pump, timing belt, pcv valve and oil pump. I have tightened back down the fiv bead as well. Before the fiv was so loose. My engine would continually surge from 1500, the to 500 then back to 1500 rpm over and over. I also for some reason have my main relay was jumped. Without these three wires or really only two conected my pump doesnt feed fuel to my injectors. If all three are hooked together the the pump runs constantly before start and while running. I cleanes my fiv and my iacv also. Im really stuck here. Please help
Thetrnas grind is probably due to a schyncro worn or wearing out also check trans fluid. Try cleaning throttle plate with choke cleaner as it may be sticking and causing your surging as well as idle problem computer sets the idle. I dont' quite understand the wiring issue unless your pgm-fi main relay is bad and someone tried jumping it.