I have an issue with my LS integra 00, maybe somebody can give me recommendations, it has a B18B1 and here it is the story:

I was on the inspection here in Costa Rica, when I was on the smog test, I tried to get the car steady at 2500rpms, and the revs started to go down and up, down and up, I tried 2600rpms, same issue, tried 1500rpms, the same, so it is not just at specific revs.

I replaced: Distribuitor cap, spark plugs, spark plug wires, ECU, O2 sensor, PCV, no vacuum leaks I tested it with carb cleaner, compression is fine, cleaned IACV, FITV, replaced map sensor, replaced TPS sensor and it is properly calibrated, timing is fine.

The only things I'm thinking right now is the coil, or maybe one fuel inyector is bad?

Cel is on and shows a misfire in all cylinders.

Important fact: I tested it with a B20 ECU and the problem doesn't happen, but it was giving to much fuel and the car was boggin, but I already tried 2 different ECUs for B18B1 (P75) and the same issue occurs, maybe is something related to fuel injection?

With the P75 ECU it only happens when the car is warm a little, like 1/4 of temperature

Need some help here, if you guys maybe have an idea
Thanks,

 

After replacing all that it sounds like the injectors I had the same problem in my f150 and the injectors were clogged try new ones or take them out and clean them the fuel pump could be blocked some as well. It sounds like the b20 ecu is forcing more gas and its getting more gas to the cylinders and the other one is signaling the fuel pump to apply as much pressure

 

Iac sensor could be bad too

 

Thanks for your response Johnoolo, today I bringed the car to a shop, they are going to test the inyectors, check the cc, and get a clean up, from something they said, could be a inyector failing giving a lean condition in one cylinder, and that is why with the B20 ecu and with a rich condition it didn't happen.

I'll check that today and see what happens!!

 

Just FYI, I changed my header that was bad, it had a leak and 2 tubes were flatted because the low car, seems that was causing the O2 sensor to read bad.
I replaced it with the OEM exhaust manifold and now runs and feels like a champ, no probems with the revs anymore.

I checked the smog on a shop and they are just fine now!!!

 

Car passed Smog test!! :D hope this thread helps somebody else.

SOLVED

 

Had same problem. Glad it all worked out for you!