I have a EG sedan with the original P28 auto ecu, auto manifold and throttle body and original z6 engine.
Recently I put in a 99 EX 5 speed transmission in the car because the automatic lost reverse gear and I have an EK parts car that had almost everything I needed (besides the engine and intake manifold and the ecu fix which I sold a couple years ago unfortunately)
The EG with the 5 speed swap drives and shifts fine but it has that dreaded idle surge, I've read everything I can find about the IACV wiring and the ecu and I'm honestly still confused, I just don't have much experience with wiring.
What I need to know is what exactly I need to do to fix this idling issue, would a new intake manifold, throttle body and rewire the 3 wire iacv to a 2 wire iacv and a manual conversion on the ecu fix this? Or is there other alternatives that are more inexpensive because I'm on a really tight budget atm with christmas coming up soon.

Cheers

 

Did you only swap in the '99 Civic EX manual transmission or did you swap in the engine AND transmission ?

 

I just swapped the trans, I still have the original Z6 engine

 

All the OBD1 is two wire you should have a 2 wire IACV already and not need to change anything there. You will need to replace ECU or move the programming resistors inside so it doesn't throw transmission codes.

 

So if I move those resistors in the ecu that should make it idle right or are there more strings attached?

 

Nope. Swapping the transmission has absolutely nothing to do with the engine function. You have either experienced an unrelated and untimely failure that is totally coincidental OR you have created this issue with something else that you have changed during the process of swapping out the transmission. Think hard... what else did you change ?

 

So I did the ecu changeover on my auto ecu and now I have no check engine lights and she idles like a dream, thanks so much for your help man