lilhatch89

So I am at a lost. 1991 Honda Civic LX, Has JDM b16a SIRII running on a JDM p30. The car wants to bog and drive like it has no power. Swap came from my 1990 Honda civic EX. I had no problems with it at that point. I swapped it into the 1991 LX after the ex was totaled. Used a Monotech plug and play dpfi obd0 to MPFI obd1 Harness. Everything seemed fine, Except sometimes for no reason the car would randomly die, I would fight with it and it would eventually start after a few tries and would not give me anymore issues for a couple of days. Afterwards I replaced the coil and igniter in the distributor. This issue seemed to stop. However it did seem to still have a hiccup when you stepped on the gas from idle. Didnt think much about it till the car started experience power loss. I would bog and loose power. I assumed the distributor was just bad so I bought a brand new one, high performance VSM one. Car ran whole 10 minutes before started bogging started, to the point the car wouldn't go above 30mph. I pulled the dizzy put my OEM Dizzy back on, car seemed fine other then slight bogging continued I could drive it again and seemed to run okay. I picked up another Brand new distributor from autozone. Brand new, not reman. Swapped it on. conditions worsened. Put the OEM back on. This time, I swapped out Cap, Rotor, Plugs, and Wires for all new stuff. NGK for plugs and wires. Condition stabilized but was still noticeable. So I tested fuel Pressure, 70PSI off the line, 40 at the Fuel rail .32 at idle. At this point, Mono built me a new harness, and we swapped it out. Still condition remained. Since then I have replaced fuel filter, Main relay, TPS, and Knock sensor. Swapped out the Fuel pressure regulator with a known good one. I have also tested both the dizzy and ECU in another car and had no issues at all. I have checked timing and its dead on at the belt. I also went ahead and swapped out the the Temp sensor on the side of the head under the vtec solenoid, as I had many people say this was the problem. No luck. I will also add that now the car is also stalling on start up on occasions. Start it and it will shut off like the key was turned off. I start it back and seems fine.

~sp33~

"mono built me a new harness"

A new engine harness? It does sound electrical.

lilhatch89

I originally purchased a plug and play harness from him, obd0 DPFI to obd1 MPFI. It was on the car for about 6 months, bogging issues started within the past month. So in order to rule out the engine harness, he built a new one and we swapped it out. So im on my Second harness from him Issue still occurs. Im really leaning towards Ignition switch. It fits with the stalling and immediate stalling after starting. Only thing i cant find are symptoms of bogging or power loss due to ignition switch.

th3pwn3r

[QUOTE=lilhatch89;51263403 So I tested fuel Pressure, 70PSI off the line, 40 at the Fuel rail .32 at idle.[/QUOTE]

Did you test fuel pressure under load? I need to do this on my CRX, having some issues and not sure if it's just my bunk tune or a pump/fuel strainer problem.

th3pwn3r

So I happened to figured out my issue, the fuel tank vent isn't working properly, I'm not sure if the two way valve is clogged or what but after venting the tank through the filler neck my fuel pressure issues are gone.