Bought a 91 CRX with a ZC swap for a few bills. Has a ton of wiring issues, so I have some questions. I am looking for some help with wiring dizzy and cps. Any kind of information, close up pictures, writeups etc etc. I have done some research and it seems that it is a obd1 wiring harness since the harness dizzy plugs are for TD43U? I am not 100% sure though. Any help would be greatly appreciated.

The car came with 2 ECUs. This PG7 that has been chipped(supposedly)


And this P72 w/ adapter harness


These are the wires from the harness to the dizzy, the dizzy wires/plugs match. I assume I have a TD43U?


This is the connector from harness to the Exhaust Cam Position sensor, it only has one wire going to it. Is that correct?


Couple wires just chilling, not sure where they go lol. Any ideas?(Coming from the baby blue wire loom)


Here is an over head shot of what I am working with.


And an overall pic of the bay


Thanks for any and all advice/info!
Tad

 

Would this have been better in the Engine Swaps forum?

Thanks
Tad

 

has the car been converted to run OBD1 (does it have an OBD0 to OBD1 ECU jumper harness)?

the engine you have was originally OBD0

PG7 ECU is OBD0 and cannot be chipped - P72 is an OBD1 VTEC ECU which will not work with the DOHC ZC non-VTEC engine - the OBD1 DOHC ZC ECU is a P29

the OBD1 DOHC ZC distributor is a TD43U which has the Cylinder sensor in the distributor - the OBD1 DOHC ZC doesn't use the Cylinder sensor on the exhaust camshaft

have no idea what the 2 unattached wires are for - looks like they are spliced onto the end of some other color wires?

 

Alright, I do have a jumper harness but it only fits the p72 to wiring harness. The PG7 ECU connects directly to the engine harness. The jumper harness will not fit it, different connectors.

This is the ECU jumper harness.



The 2 wires that are just chilling are originally solid blue and blue/yellow stripe.

From what I gather is it is a OBD0 wiring harness since it connects to the OBD0 ecu with no jumper but has OBD1 dizzy connectors?

Here is a picture of the dizzy.



Edit- here are some more dizzy pics. I have looked at pictures of both and can not tell the difference other than the plugs and the ones on mine look like they were repined. I honestly do not know which I have.



Thanks for your help!

 

Could someone tell me what dizzy this is? I believe it is a TD43U but it looks like the dizzy side plug has been repinned. So I am not 100% sure. Here are some pictures plus the ones from above.

 

looks like the OBD1 TD43U to me - the OBD0 TD03 for the ZC has only 5 wires out of the distributor into the larger connector since the distributor doesn't have a cylinder sensor in it

the ECU jumper harness is needed to mate the OBD0 chassis harness to the OBD1 ECU - plug the chassis harness into the jumper and plug the jumper into the OBD1 ECU, but you need the correct ECU - the TD43U would be the right distributor to use with the OBD1 ECU

the 2 wires could be what was added for the cylinder sensor on the exhaust cam when it was OBD0 - original sensor wire colors in the Si engine harness should be blue with green stripe and blue with yellow stripe - the external cylinder sensor isn't used on OBD1, but the original B/G and B/Y wires should be going back to the distributor connector like it was originally

 

Thanks for the reply jlicrx. The p72 ecu I have has been chipped, and it has 3 different roms with it. One of them is labeled dis vtec. I am assuming it means disabled vtec. Is that possible? If it is would that ecu work with my application with vtec disabled?