Hi everyone I'm new here to the forum but have been working with hondas for over 5 years but recently a problem has really got me stumped...

I bought my 96 civic b16 turbo back in July with an issue that seemed like it would be an easy fix. It seemed to really lack power and would only run sorta right when i had the fuel pressure turned down very low. I figured it was just a tuning issue so I purchased hondata s300 v3 and a basemap tune from HA motorsports. Well that didn't so after weeks of playing with it I said screw it. Pulled the engine and replaced it with a h23a blue top vtec engine and mated it to my current b16 transmission and got that running.

Still have the same exact freaking issue. The car will only run right if I have the fuel pressure turned down to about 20 psi at WOT and even though it runs good I can tell it's lacking at least 50% of its potential power. It feels comparable to d16z6 engines I've owned..pathetic. I've replaced the fuel pump, fuel pressure regulator (with adjustable aem), fuel filter, and inspected the fuel lines. No changes. I'm really running out of ideas so I decided to reach out to this forum. I've never encountered anyone else with this same issue and it s really driving me nuts. Any and all insight would be appreciated. Thank you in advance

 

The fact that you're driving the car around without a proper tune is beyond stupid. Take the car to a tuner. Get rid of the AEM FPR, and re-install stock - it isn't necessary (unless there's something significant you haven't told us), and the AEM FPRs are fairly notorious for being ****, even right out of the box.

Take your car to a tuner before you ruin something permanently.

 

Have you tried another fuel pressure gauge to eliminate the possibility that the one you have is reading incorrectly ??? Also, the H23 uses a larger fuel injector than the default stuff in a basemap, and I suspect your turbo B16 had larger injectors as well... this REQUIRES tuning by a trained engine tuner to optimize performance and maintain a level of safety and reliability. When you arrive at the tuners, reset the fuel pressure to stock and then tune it.

 

What ECU?
Still the same as the B16/S300? if so, found your issue...
Just like NARC said, un-**** your management...

 

AEM fuel pressure regulator is not ****. It's a good piece. Actually, you need an adjustable regulator, because then you can run whatever pump and injectors you want and set the pressure just right. But you cant drive a car at 20 psi. 43-50 is the sweet spot.

You got to tune the car. First step is to go into smanager and upload a suitable map. The hondata forum has tons of maps for free. I personally have an h23a map there that runs good. Then you need to make sure the injector size is set properly. Then you need to make sure all codes are cleared. Then you can start to fine tune the fuel. Doing these things is not much harder than posting on Honda-tech.com.

If you don't have a wideband then there's no point in trying at all because you're blind. The current tune is probably way too rich which is why it runs on low fuel pressure.