Iv got a crx with a d15b vtec swap and from 0bd-0 to 0bd-1 conversion harness in it, other then that its stock. It's been having a weird fuel problem, was wondering if anyone else has experienced this. It will start up and drive fine no problems there, when you get on the highway and get up to about 65- 70 and have a part throttle acceleration it starts to lean out and begins to miss fire very badly until i slam it WOT until it stutters out of miss firing . I hooked up a wide band to make sure it was a fuel problem and when i start the car everything looks normal but as soon as i start driving and i get up to 65- 70 its LEANS OUT TO 20:1. But here is the really weird part if i keep driving it for another couple of minutes or so the problem just disappears. The air fuel goes back to like 14:1- 15:1. Im wondering if the person that had this car before me has something weird with the wiring harness? Maybe the fuel pumps going bad or injectors? Its got to be something electrical. Please let me know what you guys think, thanks alot

 

check your primary o2 sensor that could be the problem

 

I dont think thats the problem. Iv had crx's before that didnt even have the 02 sensor hooked up and didnt cause this problem. Plus i have changed the 02 sensor

 

anyone got any other ideas