I have recently purchased a '91 CRX SI into which someone installed a B16A engine. Nice installation but it was not completed prior to the installer passing away.
Question: Where is the knock sensor supposed to be installed and where in the ECU does it plug in?

The engine installer put in a Hondata S 300 ECU installed on the passenger floor board. I have a CD with the Hondata unit but that is all.

Oxygen sensor: The B16 has a set of headers on it with an O2 sensor in it but the O2 sensor is not wired to anything. Where does the wire go on the ECU-Hondata S300?

The installer put in what I think is an aftermarket cooling fan assembly with two sets of fans. How can I see if that works other than wiring direct to the battery? I assume it has a thermostat of some kind on the fan assembly. I have not been able to find a brand name on it, so perhaps it is a factory unit? Where would the thermostat be and how should it wired up?

Any help on the above would be appreciated. Thank you in advance!

Lee O. email address is oppenheimli@gmail.com

 

Please provide more info about the setup....Is the engine stock? Boosting? High compression pistons/Cams?

This will determine which ECU you should use to run the B16.

Assuming you are using a stock engine, you must determine if the ECU and distributor is OBD1 or OBD-0. Depending on which OBD you choose, will determine knock sensor wiring and O2 sensor setup and wiring.



For the cooling fan, basically the coolant temp switch on the back of the block gets hot and grounds out and activates the cooling fan relay. The fan relay actually powers the fans. (The fan relay is on the inside fender wall, behind the headlight.)

coolant temp switch




diagram for crx without A/C

 

Thank you so much for taking your time to reply to my inquiry. I really appreciate also you taking time to supply the photos and diagrams you did.
Because the builder passed away before I purchased the car, I do not know if the cams are stock. I have some photos of the rebuild which lead me to believe the cams are the stock cams because of what appears to be some normall wear marks. The engine is not boosted.
The photos I have lead me to believe the pistons are stock and may be new. The photos show they are ultra clean. I do not have any part numbers, so short of tearing the engine down I do not know how else to tell if the pistons are stock or not.
The installation has the airconditioning compressor, clutch and condenser units installed. The clutch works but no cool air egresses fromt the vents which leads me to believe that perhaps the AC system was never recharged.
Do you have a manual and if so what is the name of it? I would like to purchase one. I realize that since my '91 CRX has an engine transplant, some of the contents of a manual for an original car would not apply.
I also have a cable transmission that was installed by the original owner.
The only ECU I see installed in the Hondata S 300.
I will really appreciate any reply.
Thank you,
Lee O.

 

 

Hi Gringo 7718,
I am getting back to you a lot late as I had to be out of town for 7 months. Please excuse my "lateness" and thank you again for your two previous replies.
Another question please, what manual are you using? I need to buy that I think. I do have a manual on a CD however I would rather use a book when I am in the garage.
My CRX has a Hondata S300 installed. I thought that it was supposed to piggy back to the original ECU. I do not see another ECU, have taken the cover off. Any advice will be appreciated.
One more, my B16A has a GR exhaust manifold. The O2 sensor is in it but not connected. Do you know if I can run a lead from the sensor to the appropriate "port" in the S300?
Thanks again, Happy Thanksgiving and an early Merry Christmas.
Lee

 

 

No problem,
If you can take pics of the ecu wiring plugs and distributor wiring plugs, that would help us determine if you are OBD-0 or OBD-1. Also throw in some pics of the pistons/build parts - it can't hurt.

If the engine is stock (not high compression/cams) then getting the appropriate stock ECU might be an easier route.

The manuals can be downloaded from here: http://hondahookup.com/manuals/
(you have to create a login, but the downloads are free.)

 

Hi Gringo 7718,
Thank you very much once again for your help.
I did download the manuals from hondahookup. Thank you for the good advice.
I think the engine is stock but I really do not know. I have photos of the build but no parts receipts or any data to refer to. The photos only show the short block pretty much assembled. The same goes for the head assy.
I guess that with the Hondata S300 the builder put on the car there is the capability of handling any modifications that were made. I am doing some research on line to try to determine what I actually have with the car. I have also looked up a lot on the S300 to see which pinout controls what components. Lots of work to do yet.
What manuals do you use? I not the photos you sent of the B16 block look nothing like what is in the manuals downloaded from HondaHookUp.
Merry Christmas and a Happy New Year.
Lee

 

Hello HondaPartsHero,
I think I already thanked you for the excellent photos with color coded highlights. If not, I apologize and thank you profusely. I am very grateful. I emailed you yesterday through your EBay store ads.
Question: Are the pinouts you highlighted on your photos the only ones I need to be sure are hooked up properly? In other words are these the ones that are different for the B16A swap from those used with the original engine?
I have some wires "pinned" into incorrect pins but am not yet finished tracing all the wires from the Hondata S300 out to the engine yet.
I have been told I probably have the latest harness because I have the white wires with the gray clip at the distributor.
I have an RC header with only one O2 sensor port. Which of your harnesses should I use?
I have a B16A engine swapped in by an owner who has allegedly passed away so I have no way of knowing if it has any modifications to it. I assume not. S/N on the block is 5009836. Any of your harnesses I should be using.
I am very willing to pay for advice and your time in emailing or telephoning.
oppenheimli@gmail.com, 520 803 9493, cell = 520 730 3402
Thank you in advance for your consideration and time.
Merry Christmas,
Lee

 

1. Determine what it is that you have.
2. Check wiring
3. Get appropriate stock ecu, or have the s300 tuned for a stock B16.

If you have wiring that looks like this, you are going to use obd1. Here is a complete pinout, so you can work on tracing each wire, one at a time and make sure they are pinned on the ECU correctly and going to the correct sensors on the engine. Take your time and go through them all one at a time.


If you have obd-0 wiring your wiring at the ecu will look like this.