2khb

b16a2 swap. when cold seems to idle/run fine. Once warmed up has a lopey idle, sounds like it is cammed - it's not, and rpms bounce between roughly 750-900. Give it a little throttle and when it comes back down it stalls out, every time. Get a 1399 (random misfire) code. Friend following me home after picking up from the shop said the fuel smell was horrendous, so, is dumping fuel too. I have checked over it numerous times and can not find anything wrong. It has been to reputable service shop to be checked out and they couldn't find anything. Said they didn't find any vacuum leaks, they tried a new IACV, didn't work. They couldn't figure it out. There is a tuning shop near by that it will have to go to next if I can't get it figured out.

The details:
2000 civic dx hatch
1999 B16a2 swap, with engine harness and ecu

before putting it in put new oem water pump, oem type r oil pump, oem timing belt, baffled oil pan and oem N1 ctr crank pulley.
new throttle position sensor
new fuel pressure regulator
only added catch can, remote fuel filter set up.
new radiator
new clutch
new lightweight flywheel
secondary o2 is wired in

JRCivic1

The fuel line between the fuel filter and the fuel rail... is it from the original DX engine or did it come with the B16A2 ??? If it isn't from the Si, this could be your problem. Also, your valve adjustment could be too tight... operating fine when cold but once warmed up, grows a bit and hangs the valves open slightly causing low compression... and thus, misfires.

2khb

I think that fuel line is from the si. As far as the valve adjustment, the car the motor came out of I was driving before I took it out. Ran great and I did nothing to the internal so, nothing should have changed. That shouldn't be a issue.
On second thought that line is from the dx. Those lines can't be that different?

JRCivic1

Oh but they are my friend... try the Si fuel feed line and see what happens. If that one is unavailable, you can substitute a '94-01 Integra (any trim level... LS, RS, GS, GS-R or ITR) or a '92-95 Civic EX fuel line WITH the washers at the fuel rail end.

2khb

Have not tried the fuel line yet. Have been researching the p1399 code, if correct from what I have researched is a code for faulty ignition control module. My question would be then if the control module is bad would only rear its head when the warmed a little, a couple minutes, then get the rough idle and stalling when giving it a little throttle. Or could the stalling issue be a cause of the a bad ect sensor? In essence having two issues at the same time or will a bad module cause this on its own? Below are a few videos of it running

Cold Idle:
https://drive.google.com/open?id=1Lf...4VreC744gZHiNL

"Warm Idle":
https://drive.google.com/open?id=1o2...4ZWrIuJSdwNOYI

Giving it gas and trying to keep it running:
https://drive.google.com/open?id=1GT...Vl7GVmAQwV4h5g

Free Man