kenbahn

advice please:
i've got an '04 civic SOHC A/T (EGR). threw a rod so replace w/ '03 (i think) engine w/o EGR. have driven fine for a year+ now w/ CEL on only for EGR. so, now i'm ready to change ECM and pass emissions inspections.
1. I can simply swap in an ECU from a SOHC non-EGR 7th gen civic? then reset by pulling ECM fuse, or running and idling?
2. what's the route i take to replace ECU if not as stated above?

will the car even start and allow it to "reprogram" the ECU once i make the swap?

thanks y'allses.

ezone

Any PCM replacement will need to be programmed before the engine is allowed to run, so that's a dealer visit and some loot.......
BUT.......
You should not use a 01-03 PCM in a 04-05 car due to significant wiring, component, and sensor differences.

All 04-05 engines were equipped with EGR.




Your engine swap was block/head/intake only? Still using the 2004 wiring harness and exhaust and O2/AF sensors?

I'd say it's gonna be a lot simpler to swap the coolant housing (with EGR valve) and the intake manifold gasket (if necessary) for EGR equipped versions from the original engine (or used).

kenbahn

i've been told by so many people over this last year i could easily swap ECU/PCM to make this work out.
maybe i could reroute a few wires? though i don't wanna get too deep on all this.
what if i were to install an '04-'05 D17A2/V-TEC block/head? could i get the corresponding PCM and leave wiring in place and reinstall sensors? thanks.

ezone

Wouldn't it be simpler to just install the missing pieces so your 2004 computer will be happy?
It SHOULD have been done during the engine swap in the first place a year+ ago, now you just have to make your installation correct.

Also, you didn't tell how this install was done. Is the original 2004 LX wire harness still in use?

kenbahn

i couldn't disagree that it would have been easier and should have been done. i'm a total hack mechanic assisted by more experienced hacks. it hadn't occurred to any of us to bother with the EGR and intake manifold. the old block and rest of parts are long gone now.
yes, same everything else in the '04 including wiring harness.

sounds like a trip to the parts yard for the coolant housing would be worthwhile. if not too much, please post links to the specific parts i need and i'm figure it out from there.

thanks for corresponding and pertinent advice, ezone.

ezone

Best I found quick is from a parts catalog...

From the end of the cylinder head you would need, in as large a chunk as possible:
Housing #8 and gasket #9,
housing needs to be complete with as much attached as you can get from a junkyard engine including EGR valve, thermostat, temp sensors, pipe #11, clamps, fasteners/nuts/bolts, etc. The more you can grab, the more spare parts you have later on LOL






For the intake manifold you should only need to swap to a gasket intended for use with EGR, the upper gasket pictured has all the extra holes for use with EGR...bottom gasket is for use without EGR.

John Motley

What was your solution to your egr problem. What did you have to do i have same exact problem

mac25

He had to swap the egr parts onto the non egr engine.

01-03 cars run narrow band O2 sensors, 04-05 run wideband, among other differences, but that alone means an 01-03 ecu will not work in a 04-05 car... without wiring changes.