I have a 91 crx dx. the engine harness in it is FUBAR. I know a si engine harness will not work because it will not plug and play into the dash harness. but my question is will the si engine harness work if I use both the engine and dash harness?

 

No. What you will need to get the si engine harness is a complete matching si main harness which connects to the ecu

 

Well I can get the whole wiring for a very good price. Just wondering what I would need and how difficult it would be to use the si harness

 

your best bet would be to swap the entire harness. i did this with my crx. but be prepared for a headache if you dont keep track of where each plug goes.

 

Thanks for the help. Just wanted to know it was possible before I got into this and made a bigger problem for my self

 

first, what is wrong with the current stock harness that makes you want to swap out the entire harness.

 

the guy that had the car before me wired it for his b series and messed it up. he took it to a shop in the houston area and they did what they said is a "mild tuck" but looks horribly done. they eventually pulled out the b series and then ended up cutting some connectors. i was also told the shop did something with the dash harness to the point where everything is connected directly to the ecu. i could take some pics of it if needed

 

It's missing injector clips and other clips as well

 

Hmmm...
If the plans were to convert to OBD1 then now might be a great opportunity.
It's a wiring marathon, but you can hardwire the OBD1 connectors for the ECU and change out your firewall plugs to mate directly to an OBD1 engine harness.
If you have the know-how to read wiring schematics and are good with wiring then it can be done. If not, then I wouldn't suggest attempting it because you will have no help other than yourself.
Replacing your dash and engine harness with stock OBD0 stuff is much easier.

 

I can build you a harness. Check my sig below for pics if my work.
Txt me if you have questions 916-541-5266