I just recently got a 1990 integra with a B20b JDM swap, it had a chipped P06 ECU and it ran like garbage, I just bought a stock P75 ecu and when i installed it check engine light instantly came on, checked codes and it gave me code 2 and code 5. i bought a CRV map sensor and installed it and although the car ran slightly better it still threw the codes, code 2 i think is from me having the o2 hooked up to my Wideband AFR guage and that is also the only o2 sensor i have. the problem i am having is the car is lean unless i give it a good amount of throttle and when i mean lean it is off the Stoic charts, over 18.0. the swap appears to be done really clean and nice and i don't hear any vacuum leaks. how can i get my car to stop running so lean? what do you guys think it could be? i just want the car to run good, if i stab the gas and let off it goes rich. under full throttle i get around 14.7 AFR but if i let the car idle or i'm not giving 50% throttle or more the car is running lean. any advice and tips would be greatly appreciated as this is my first honda motor car.

 

Also i have read on forums that i can add a adjustable fuel pressure regulator, i was thinking about getting this one. https://www.newegg.com/Product/Produ...9SIACUS5DJ3190 . will that work? and will it allow me to increase the fuel pressure so my car is not running so lean? i have never used a FPR before so i have no clue on how they work

 

What injectors are on it?

 

I’m not too sure honestly, they look stock. I have no clue which ones they are tho.

 

Are you obd1?

 

Yes I’m converted to OBD1 with a jumper harness I’m pretty sure. I’m running a OBD1 p75 ecu

 

Have you done an idle learn procedure?

I'd take out the wideband and put a stock o2 sensor back in if you are on a 100% stock ecu.

 

The car did not come with the stock o2. It came like this with the wide band installed

 

And also no. I haven’t done a lean idle procedure I don’t know what that is

 

Google it, or search through the FAQ sections here.

Basically put the ECU in diagnostic mode, I think unplug the iacv, set idle rpm with the screw, plug in iacv, take out diagnostic mode, let it idle...I'm rusty so find a write-up for it lol.

 

Put the ecu in diagnostic mode aka jump the two prong wire harness???

 

Yes

 

Get it tuned !!! There are too many variables to expect that a basemap will run the engine properly. First, defeat the CEL/codes and then get it tuned.

 

Wait wait wait... You can’t hook your wideband up as a substitute for an oxygen sensor unless a) the wideband you are using has a simulated narrowband output and/or b) the ecu is programmed specifically to use the wideband sensors. The two signals are not compatible. Disconnect the sensor output from the ecu and see if that changes anything. Then get tuned.

 

I was thinking it sounds like he has the signal wire from his stock narrow band sensor routed to a wide band gauge, and no longer to the ECU.

OP - If this is the case, re-route the narrow band signal back to the ECU. A wide band gauge hooked to a narrow band sensor does nothing except give you a dazzling light show. Please be aware that the narrow band signal wire is shielded. The shielding needs to be grounded, and the signal wire must not be crimped/soldered/attached in any way to the shielding surrounding it.

 

Re-reading again, I think that is correct. What do the plugs look like?

 

plain and simple, you need to get it professionally tuned

 

Why do people keep suggesting to get it tuned?

It's on a stock p75. The engine is not modified to need a tune.

He's not running super lean because it has a bad tune. He's running lean (he's assuming it's lean because of blinky lights) because his car is not correctly wired with the correct parts.

OP, fix your wiring problems, troubleshoot the codes, move on from there.

 

because it's a JDM b20b on a stock USDM b18 ecu. It is not the correct mapping in that ecu for that motor

 

While you are correct, it's fine.

Case in point, my bro has been running a JDM b20 in his 1991 Integra on the stock ECU for about 8 years. Passed referee and smog every time, never had a single issue.

It's not like this guy is using a p28 and the mapping is way off. Plenty of people are using a pr4/p75 with a b20 to pass BAR and smog in California.