hav a 98 dodge 2500 with a 5.9L i jus replaced the engine with one from a 95 model. We hooked eveything up jus how it came factory and after we started it, it idles like crap and when you hit the throttle it kills out, any ideas on how to fix??

 

the new engine is obd1, and your truck is an obd2, the pcm is trying to read things that arent there and making adjustments, which are making your motor run like crap

 

Did you swap the intake manifold? If not, you could not have hooked everything back up. If you did swap it, clean the TB and IAC and read this, https://dodgeforum.com/forum/2nd-gen...um-thread.html

 

any idea how to fix the obd2 to obd1 swap easily? or will i hafta get wiring for obd1 and install

 

All you have to do is swap the intake from your old motor. And read the link I provided.

 

i hav swapped intakes already

 

Then read the link. And try cleaning the TB and IAC. Also, did you remove the crank sensor and reinstall after the swap? It is easily damaged, and the wires can get pinched between motor and trans. But , I suspect a clogged cat. Unscrew the precat o2 and see if it runs any better.

 

crank sensor was reinstalled fine and ok ill try that thanks