| The problem: I've been having an issue with high idle (around 1100 rpm) that's combined with a slight miss, noticeable at idle and more noticeable when trying to hold revs at any specific rpm (e.g. you bring it to 2500 rpms and leave it there, it will stumble, drop 100-200 rpms and recover). I also have some slight hesitation (or maybe more accurately, a "dead spot") when cruising at low rpm. In neutral, if I blip the throttle slightly, I don't get a crisp response instead the engine hesitates for a second then revs. When I unplug the IAA or choose "set Idle" with consult, the idle does not change at all, which I've seen in some service articles points to a vacuum leak and yet my boost leak tests have all come back negative. What I've done so far: It's been a decade since I rebuilt the engine so I went around and replaced all of the old vacuum hoses and caps, ran several boost leak test, and recevied good results Power balance test confirmed all cylinders are operational Ohm checked the injectors with good results removed and replaced the spark plugs adjusted the TPS (for whatever reason it maxes out at 3.96V, not sure if that's a big problem though) balanced the throttle bodies replaced the air regulator with a known good unit Checked the MAFs, found one was slightly out of spec so replaced it, Currently, both MAFs seem to be in the correct V range on the signal wire, although when I unplug one, nothing really happens, when plugging the other, the engine dies. I'm using a gen1 Selin translator Checked o2 sensor read out with Consult (for some reason I'm only getting 1 o2 sensor read out instead of 2?) but it sits at around 80% at idle, when I blip the throttle it will go all the way back to around 10 or so and will bounce back and forth if I hold revs at 2500 rpm Confirmed the coolant temp sensor is working. Car set up: 91 z32, original TT complete engine rebuild with a few thousand miles on it all "deletes" completed, including PCVs, EGR, TB coolant lines, carbon cannister, etc Nismo 740cc injectors, dual maf setup with selin translator, LS coils/PTU and harness delete, stock ecu with eprom tune, and a bunch of other stuff that probably isn't relevant to this issue. I'm pretty much out of ideas at this point on where to focus my diagnostic efforts... any ideas?
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