Just as the topic says, I'm swapping out my engine after a spun bearing in my 93 Prelude Si, and I was curious if the H23a1 and the H23a3 have the same wiring harness.

I'm having a mechanic friend of mine doing the swap for me as I haven't the time nor tools to do it myself.

Anyway, my friend Glen just called me up to say that the wiring harness will have to be completely replaced. And many of the sensors, etc. are not hooking up to the H23a3.

I could have swore the two engine were 100% compatable. So are they different? Will the old ECU work and everything?

 

what model is an h23a3 from? I assume its a european model?

 

H23A3 is from EDM Accord SRi.
The harnesses are the same except knock sensor which is non-existant in A3 (90% true).
A3 will have an internal coil dizzy, but you can use A1 dizzy instead. The rest shoul be the same.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pentaq &raquo;</TD></TR><TR><TD CLASS="quote">H23A3 is from EDM Accord SRi.
The harnesses are the same except knock sensor which is non-existant in A3 (90% true).
A3 will have an internal coil dizzy, but you can use A1 dizzy instead. The rest shoul be the same.</TD></TR></TABLE>

see this is why its good to have people on here from europe

 

yeah, not Sri, but iSR
KS is non existant, but the whole harness in A3 is Accord-way not Prelude-way (I have just checked) i.e is coming across the engine bay- one end is going to ECU and the other to the underdash fuse box. Use your A1 harness then and A3 ECU.

 

So the A1 harness will work if I just switch the ECU? Assuming I need this car by Friday, and I don't have an A3 ECU, if I just change out the wiring harness, with the A1 ECU work?

 

teh a1 ecu will look for a knock sensor. so you would need to make sure that is wired, or else code 23 will show all the time.

 

I'm sorry I didn't quite follow that.

Wired in what sense? I can't exactly put a knock sensor in there. Do you mean just supply the sensor harness power?

 

Hmm, not sure I buy it. The previous owner of my car had the engine replaced with the A3. The receipt says nothing about a new ecu or wire harness although theres a slight chance they just included it all in the price of the new engine. I've heard of others getting the A3 and never heard of this problem before.

 

h23a1 ecu requires knock sensor. according to the guy that is familiar with the h23a2 it does NOT have a knock sensor, meaning no sensor and no wire for it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by v4lu3s &raquo;</TD></TR><TR><TD CLASS="quote">h23a1 ecu requires knock sensor. according to the guy that is familiar with the h23a2 it does NOT have a knock sensor, meaning no sensor and no wire for it.</TD></TR></TABLE>

There is no place to put KS as in this place the oil pressure sensor is mounted.