Hello and thanks in advance for any help! Recently took on a project to learn a thing or two and replaced the engine in a 2001 Honda CRV. The engine was a JDM B20B, it did not have a crank sensor (CKF) so I bypassed it at the ECM using this technique: https://ff-squad.com/wp/?p=309 Instead of a clip I used a jumper wire and soldered everything together for better continuity.
Managed to get everything back together and it started right up, but could tell right off the bat that there was an issue, it was running real rough at first and shaking the car a bit and idle was fluctuating a bit, when I revved the engine up a bit (over 1000) it smoothed out some. I did the timing and took it for a spin. It seems that it has random but constant misfires at the lower RPMs (around 2000 and below) and especially when under a load like accelerating. Can hear it popping as I drive. It also has very diminished power, super slow to accelerate and barely makes it up my driveway which is a fairly steep hill. It continues to be a bit of a rough idle (shakes the car a bit), but holds at about 750 after it is up to temp which is on par with what the manual says is correct. I have taken the valve cover off about 4 times now checking and rechecking the timing, all marks are right on point and confirmed that TDC for Cylinder 1 was right on with the marks. I've gone through and put each piston at TDC for he ignition stroke and adjusted the valves per manual (.004 for intake and .007 for exhaust) For this I ended walking off the valve screw nearly two turns for every adjuster screw consistently. I've adjusted the throttle cable. Checked for vacuum leaks by pulling the intake hose off the throttle body and blocking the upper port with a finger and the engine began to slow and stall. I've tried two PCV valves, both I have no reason to believe there is anything wrong. I've done the ignition timing a couple times and it is lined up perfectly with the red mark. Using the ignition light I have confirmed that there is a current going through all 4 wires to the plugs and the wires and plugs are all new. When I pulled the plugs after about 6 miles of driving down the road, cylinders 2 and 3 seemed fairly normal maybe a little more carbon than there should have been after only 6 miles, but cylinders 1 and 4 were completely coated in black carbon. I tried swapping around the fuel injectors 1-2 and 3-4 to see if it made a difference and it did not. Everything seems to point towards a timing issue, but it just seems like I have confirmed it can't be that, by checking ignition timing, all marks are dead on, even after driving about 6 miles on both cams and crank, I've checked clearance on valves at TDC for ignition stroke on all for cylinders and they are all closed at TDC. I've also checked compression, it was about 175 for all cylinders and actually a few PSI higher on cylinders 1 and 4. Is it possible that the ECU is different for the 2001 CRV and the B20B engine I swapped in? Looking for suggestions on what I might try next. Check engine light has remained off this whole time except when I unplugged the IAC valve to check the idle it came on immediately with an IAC code that didn't come back when it was plugged back in and codes were cleared.

 

I'm having a similar issue with an 03 k24a1. Put a new head on it, new sensors except the crank sensor, new vtec and clean up on the vvt. New plugs as well. Now I'm thinking one of the Coils is only working about 20% of the time and causing some issues. I keep fouling plugs like crazy though. So maybe check your continuity on your coils with a multimeter/voltmeter. I'm headed to autozone to pickup a new coil and test my theory.
Theory 2: after talking to a Certified Honda Master Mechanic he believes it might be an injector issue and it would make alot of sense. So there's another place to check for you. Maybe the injectors are giving you too much or too little fuel, and you're not able to find an issue because there isn't a true mechanical problem, just too rich/lean.

 

Thanks for the reply. I've figured it out and as I suspected it was my own fault. Either my manual was talking about another model or I misread it, but I though with the tongue and groove connector between the distributor and the cam shaft I thought was asymmetrical and only fit in one way, turns out it can actually fit in 180 degrees also... Well it gets more exiting, somehow I had the wires swapped on cylinders 2 and 3 as well, so it was actually firing normally for those two cylinders with the distributor 180 off. Once I got it all back around it fired up, but was still having some intermittent misfires and occasionally when the key was turned to on position it would make a loud buzzing behind the dash, the gauges would go nuts and it wouldn't start. Turns out that sound was coming from the main relay and the issue was a bad connection on the ground at the thermostat. Took it off sanded it down and tightened that that fixed that issue. Cars running great now!