A few weeks ago my vehicle started misfiring, my OBD scanner said cylinder three misfire, and two bad o2 sensors. I replaced all the coil packs, plugs, and the two downstream o2 sensors. I also went ahead and replaced the intake, plenum, throttle body and EGR gasket(s). It ran great for about a week then started missing again. No CEL but scanner said cylinder four misfire. So I replaced all the injectors and o-rings, and moved cylinder four coil pack to cylinder five. When it is cold it runs fine but when it warms up it starts to miss, every so often, and has multiple misses in a row, after switching the coil packs the next day the scanner said cylinder five miss, so I checked and changed that coil pack. Again ran fine when cold missed real bad when warm, and especially when accelerating. I changed out the MAF, fuel pump, fuel filter, throttle position sensor, and the vacuum is at a steady twenty, quick throttle bump and it goes to two, back up to twenty five to twenty seven, then back to a steady twenty. At this point I am not sure where to go from here, could it be the catalytic converters, EGR or coolant temperature sender?
Thursday, November 12th, 2020 AT 8:56 AM