HI, I have a Civic 2004 LX stickshift non vtec.
The engine in it broke down so I had to replace it.
I got it replaced with the engine from a 2001 Vtec with the Vtec wire harness for the Vtec but it was from an automatic.
So now there is a few problems. The Speedomer and all the cables for the transmission do not fit since I have a stickshift trany and the one that came with the engine was automatic.
The car starts fine and runs great with the exception that it will only run with the regular non Vtec ECU from the original engine.
If I connect the Vtec ECU that came with the car then it will not turn On at all their is no electricity to the sparkplugs so it wont start.
I have used 2 ECU's for Vtec but it will do the same thing with Both. Except when using the non Vtec ECU then it starts but off course the Vtec does not work.
Does any one know what can I do to fix this issue?

 

It's because your keys don't match the vtec ECU, and the Immobilizer System is preventing it from running. The transponder in your keys needs to match the Immobilizer and ECU in order for it to work. You'll need to take it to a dealer.






Edit: Okay, about the transmission. Can't you just swap the VSS and such? The clip 'n' strip method? Sorry I don't have a definite answer for you. I was hoping (after 44 views now) that someone would have helped.