I tried the tech forum but got no help.

I just put a 99 ex head, ecu, and engine harness in the 96 hatch. My problem is the tach and speedo are inop. One of the o2 sensors plugs into the floor harness of the ex. And the radiator fan did not want to come on so we wired it in with the a/c fan. If anyone has experienced this a point in the right direction would be awesome.

thanks in advance
tommy

 

any CELs?

 

havent been able to pull them but to start there are o2 codes cuz theyre just tied off, there's a knock sensor code cuz I might have forgot to swap it over. And theres some misfire codes. Those are just what I know are on. I had to give the actron back to my old job. I may run up to autozone and let them pull it for me.

 

you check your fuses?

 

under the hood. it was late and we were cold. Are there fuses for the tach and speedo? The cluster lights up and fuel gauge and temp gauge work, just the tach and speedo inop

 

oh yeah and the vss is plugged in

 

is you block a Y5 or Y7...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mugencivic4dr &raquo;</TD></TR><TR><TD CLASS="quote">is you block a Y5 or Y7... </TD></TR></TABLE>
What's a y5? and why should it matter?

bump because i dont know

 

Did you use the 99 engine harness? If so, that is your problem. The 99-00 Civics have one of the ECU plugs moved into the dash wiring. So using an OBD2b harness in an OBD2a car you are missing the plug entirely. This plug powers the fan, the secondary O2 sensor, and the vapor purge systems, etc...

If you did in fact do this, the solution is to modify your original harness. Just add the VTEC wiring from the 99 harness and do the IACV plug change and you're set, also you need to sell/trade the 99 ECU for a 96-98 P2P model. Or convert to OBD1.

 

It's a y7 block. I went out under the dash and found an "instrument light" fuse that was blown. I replaced it and it blew again. So I am gonna have to find the short. YAY. Unless someone has seen this before

tommy

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by klungemonger &raquo;</TD></TR><TR><TD CLASS="quote">Did you use the 99 engine harness? </TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HamsterStyle &raquo;</TD></TR><TR><TD CLASS="quote">I just put a 99 ex head, ecu, and engine harness in the 96 hatch.</TD></TR></TABLE>

and that shouldn't be his problem.. if he's using a 99ex harness with a 99ex ecu, there shouldn't be ANY problem at all. that's basically swapping everything over from the 99. the blocks aren't much different (y7 has a bit lower compression pistons, not by much)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vsm98civic &raquo;</TD></TR><TR><TD CLASS="quote">
and that shouldn't be his problem.. if he's using a 99ex harness with a 99ex ecu, there shouldn't be ANY problem at all. that's basically swapping everything over from the 99. the blocks aren't much different (y7 has a bit lower compression pistons, not by much)</TD></TR></TABLE>

That is not correct, and I speak from experience. Did you read my explanation or were you in too much a hurry to point out that I missed where he mentioned the harness already? It does not matter if you have the 99 ecu, one of the ecu plugs is missing from the dash harness in the 96!!!!

Also, once the Y8 head is on compression is the same. But the Y7 is also missing a knock sensor so he'll get a CEL for that too.

 

I can swap the knock sensor from my other block. Is there any way to make the 99 harness work? Or do I need to get a 96-98 ex harness? I want to try not to hack up the 99 harness as it is out of my 99 ex with a bad block. I may need the harness for another swap.

 

Get the 96-98 harness, you can't make the 99 work in your 96. The 99 ecu will not work with the 96-98 harness either so you need a 96-98 ecu...OR...get an OBD2a-OBD2b conversion harness, but that costs more than a P2P ecu so doesn't make much sense to do that.

 

So I need a 96-98 ex engine harness and ecu? Will that harness have the o2 sensor plugs at the front of the engine bay? And it will work with the 99 head?

Thanks
tommy

 

[QUOTE=klungemonger]

That is not correct, and I speak from experience. Did you read my explanation or were you in too much a hurry to point out that I missed where he mentioned the harness already? It does not matter if you have the 99 ecu, one of the ecu plugs is missing from the dash harness in the 96!!!![QUOTE]
I misread your original statement, chill.

I stand corrected

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HamsterStyle &raquo;</TD></TR><TR><TD CLASS="quote">So I need a 96-98 ex engine harness and ecu? Will that harness have the o2 sensor plugs at the front of the engine bay? And it will work with the 99 head?

Thanks
tommy</TD></TR></TABLE>

Yes that is what you'll need and it will work with the head. The EX has only 1 O2 sensor plug at the front of the engine bay. This is the important one anyways. EX and Si models have the converter underneath the car and the secondary O2 plug comes from the dash wiring and drops down out of the car near your shifter.

You might want to do this though:
Use your original Y7 harness and modify it to work. You need to change the IACV plug, but there will be a wire left over which you can put in for the VTEC pinout. If you don't have emissions testing you can use the secondary O2 sensor wires for the VTEC pressure switch and one wire for the knock sensor.

If you are able to go OBD1 that's a good idea. Because OBD1 doesn't use several of the sensors you currently have, you can reroute those wires to use for VTEC without getting any CEL's, and save the $100+ on the EX harness, also OBD1 ecu's can be chipped. There is a tutorial page available on how to modify your harness to run VTEC.

 

Thanks for all your help. I think i am gonna just get the 96-98 harness and ecu because we had problems with my cx harness. We had to rewire a few things. Plus I like to do things right, thats just me though.

Once again thanks for all the info.

tommy

 

Good luck. I will be doing my mini-me swap on my 99 dx in a few weeks. Just waiting for the ecu and some other parts to arrive.