2.3L ('83-'97) 2.5 swap problems

[austinsford]

Hey everyone, i have a 1996 ranger 5 speed i bought with a bad engine. I built a 2.5 engine, i have ported the head, and milled it .030. I am having a problem with a rich code and it will stall on decel untill it gets into closed loop. New maf, coils, 02 sensors, fuel pump,PO deleted cat (i will replace once it runs with no codes but it is not throwing a cat code). I drive this truck daily and the plugs read find. I am at a loss for this rich code. Thank you all

 

[scotts90ranger]

So what are the fuel trims doing when driving at different speeds and loads? There's two ways of interpreting the codes, is it running too rich or adding too much fuel? Watch the short term and long term fuel trim values, I use Torque Lite with the cheap blue things with both on gauges showing high and low values on the same tab. Pay attention to both at no load idle and say 2k rpm while driving in each gear at steady speeds. Since I'm not sure if it's adding too much fuel or taking away too much fuel it's hard to recommend what you might need to do.

One dumb thought is fuel injectors, are you using the ones from the 2.3L or 2.5L? They're different not to mention a '96 is set up for lower fuel pressure and a return and regulator on the fuel rail and the 2.5 is returnless.

 

[austinsford]

I have new 1996 2.3 injectors in it, my brother took my code reader that let me check fuel trims and left it in the car he scraped... I will buy a new one but the good ones are just expensive. Everything like the manifold and sensors are off the 1996. Thank you