99CcordMTF23

Alright folks, prepare for a read and a half....
My car, 99 accord cg5 sedan. Engine, 2000 h22a4 obd2, external coil dizzy. Ecus obd1 chipped p06, obd1 p13 jdm h22.

The engine was new when installed. Timing is spot on. Has brand new ngk iridium plugs, brand new td77-u distributor, brand new ignition coil, brand new map sensor, new iat sensor, new fuel injectors (obd2 290cc saturated, still runs rich), new o2 sensors, boomslang conversion harness. No itb, knock, egr, fitv.

Here's my problem, and it started out small and got worse over the past year. It has a bog/misfire around 2-3k rpms. I have literally tried everything I can to resolve this issue. The weird part is, when map sensor is unplugged (in limp mode) it doesn't do it as bad and will idle at a steady 1300rpms but sounds like its groaning and exhaust note gets very deep, runs crazy rich and I get black smoke out the exhaust. Limp mode I figured would be running off the ROM, but apparently it seems to do strange things to the overall tune. Sensor plugged in, part throttle 2-3 rpms it has NO power, literally sounds like it is shooting ducks. I have replaced every damn sensor on this thing except tps but it does it no matter if its plugged in or not (it was tested and adjusted correctly) its got 195psi on all four cyl (I'm at 7900ft elevation), valve clearance is in spec, timing is spot on, fuel pressures are steady at 45psi on my gauge (85 when dead headed, still idles like ****) all ignition parts are new except plug wires which ohm out. (OEM Honda wires). I'm literally stumped. With the p06 and chip I don't get a cel or any nonsense like that except when its cold I get a 68code. Ecu fault. Its terrible to start cold. And has always had a stumble and misfire at idle...

My only thought could be; with a jdm ecu/ p13 basemap on the p06, could it be the fact that I have crank sensors on the block, and not in the distributor like on the jdm h22a engines? The extra few inches of wiring could be causing a false signal? It stumps me because at wot it will pull through the bog slowly, clean up, hit vtec nice and loud crossover but it breaks up like static after 7k rpms. Has no *****, unplug map sensor and throw it in limp mode, it will pull better but nets 10.4 mpg and still misfires. I have tried the obd2 map sensor on the throttle body, and an obd1 map remote with vac line. Both new sensors, no change.

Any ideas? This is literally driving me crazy. I've done plenty of Honda swaps and have been a mechanic since I could walk. Lol I don't want to have to tear this beauty apart...

99CcordMTF23

I figured I would ad I have no cat, so its not clogged. And the misfire is worse with the jdm p13. (I get all the emissions codes but I expect that since none of the stuff is there) Its so bad it will just die pulling onto the highway now, when I get her moving it will backfire out the intake and the exhaust . Car is parked and my da9 teggy is pulling daily duty.

I had a usdm p13 ecu that I used, and it was worse than my first two.
No vacuum leaks, no gasket issues, nothing.

I'm literally losing my mind on this one. I say misfire, I mean engine sputters, slams back and forth its missing so bad, backfiring out exhaust and occasionally intake. It will just die, ect. When I pull the plugs they look fine. No carbon build up or any fooling. Nice light Brown on the ceramic. They are gapped to spec aswell. Trying to cover all my bases here. Oh! Also, a new main relay and ignition harness on the chassis.

hybridmiklo

Is this thing dyno tuned? And is it running open loop or closed loop?

99CcordMTF23

Closest dyno tuner is 3hrs away. No I haven't had a tuner look the ROM over. But. It will run the p13 in open loop mode while cold, but the symptoms are slightly less severe, with only stalling just off idle, until it switches into closed loop gets sensor feedback, then all hell breaks loose. The p06 was a shitty "dyno tuned" map. All I asked for was a stock map but I guess not... anyway, it has the same symptoms. I assume its a sensor issue I overlooked or missed... I don't see it being mechanical as I have literally checked every spec possible and all are fine. I mean, my motor had never even ran or had oil in it before I got it. I must be missing something...