just want the 240 to run right

[240user89]

someone pleaae help to the best of their knowledge. just did a engine swap from a ka24e to a ka24de last weekend and when i got it in there it ran but it ran like crap when you start out. now my question is could it be my o2 sensor thats bad to make it run bad and then run right normal in higher rpms or what could that be. oh and i know i have an exhaust leak if that could have anything to do with it. please someone help

[240user89]

come on someone help me out

[Wc240]

you need to start with the basics. battery cables/terminals good and tight, fuses good. timing, EVERYTHING hooked up right. right ecu. if your eshoust leak is BEFORE the o2 sensor then yes, thats gonna tell the ecu that your running very lean and to dump fuel.bad o2 sensor(if your sure its bad) can couse it to run rough, but, i would suggest this:Check the basics that i stated, then look on nico for the FSM and look for the base timing/idle mixture adjustment procedures and follow those to the T. If your pretty sure your o2 is bad, theres a way to find out. the same place in the fsm where youll find how to read codes is a test to see if your o2/ecu is in fuel control.goodluck

[240user89]

so your saying it could be my exhaust leak thats making it do this? because we checked timing and all the basics and everything is in time and all that good stuff ecu is good but the o2 sensor is all kind of banged up and dented and stuff like that