B18C Auto W/ p72-901 ECU BIG problems

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rdomeck

rdomeck

New Member
I have been working on my wifes 98 Civic trying to put a GSR engine and Auto tranny in for a while now. Mostly it's been sitting in my way as we just became parents of twins. I have made all of my own mounts and tried to figure out the wiring of that dreaded P72-901 ECU. I can't find anyplace that has a pinout of that damn thing.

I have actually been able to get the car running and driving on that ecu, but I have the following problems.

-Only has 2 speed's 2nd and 3rd. When it shift's it slipp's really bad.
-Check engine light on
-Alternator not charging
-When I press on the brake pedal to shift it doesn't unlock the selinoid to be able to shift out of park. I can use the key in the slot to get it to release!
-Speedo not working

I think I'm close, but still far away

The bastards at Nagasaki Motors in Canada really screwed me on this one. They didn't send half of the parts that they should have and I believe they sent me a bad transmission.

Man I really need some help. I have had many Honda's and I run an Automotive restoration business. I also spent 10 years installing computer and telephone networks. I'm not scared of wiring at all, but need a idea where to start........

Please help

Thanks Randy
 
rdomeck said:
I have been working on my wifes 98 Civic trying to put a GSR engine and Auto tranny in for a while now. Mostly it's been sitting in my way as we just became parents of twins. I have made all of my own mounts and tried to figure out the wiring of that dreaded P72-901 ECU. I can't find anyplace that has a pinout of that damn thing.

I have actually been able to get the car running and driving on that ecu, but I have the following problems.

-Only has 2 speed's 2nd and 3rd. When it shift's it slipp's really bad.
-Check engine light on
-Alternator not charging
-When I press on the brake pedal to shift it doesn't unlock the selinoid to be able to shift out of park. I can use the key in the slot to get it to release!
-Speedo not working

I think I'm close, but still far away

The bastards at Nagasaki Motors in Canada really screwed me on this one. They didn't send half of the parts that they should have and I believe they sent me a bad transmission.

Man I really need some help. I have had many Honda's and I run an Automotive restoration business. I also spent 10 years installing computer and telephone networks. I'm not scared of wiring at all, but need a idea where to start........

Please help

Thanks Randy
Click to expand...

i hear ya..im puttin a b18c into my del sol..and wiring my ecu is going to be fine, done alot of electrical in my time, but i cant find anyplace telling me what goes where, why it goes there, and stuff like this..im sure there are alot of people out there that need this info..someone point out a thread and help us out!!
 
You need to run an automatic integra LS ecu, and wire vtec to a controller. As for the your speedo not working, you will need an automatic speed sensor from an automatic integra. As for the shifter locking in park position, I would go the easy way and just break the lock mechanism.
 
Any idea what year I should be looking for and where I could find pinouts? I believe that I recieved an OBDI engine and ecu when I ask for a OBDII. I can't seem to even find that information on line about that ecu. I will be glad to switch ecu if I have to, but I feel that I'm close to making this one work with a little help! I'm already to much money in to this swap. I should have just rebuilt the old D series. I hope all of this is worth the effort!

Thanks for your help
 
If its obd1, try and find the transmission from a 94-95 acura integra LS/RS/GS, as well as the the ecu from the same car.
 
LS_VTEC said:
You need to run an automatic integra LS ecu, and wire vtec to a controller. As for the your speedo not working, you will need an automatic speed sensor from an automatic integra. As for the shifter locking in park position, I would go the easy way and just break the lock mechanism.
Click to expand...

Is it not possible to use the actual automatic JDM ECU? That seems like it would make the most sense...
 
He can try, but he doesnt have the automatic jdm transmission with it, along with the VSS and harness.
 
if you're running a obd1 auto trans, you have to use and obd1 ecu.. and vice versa for obd2, because the tcu is different for each. that might be your tranny problem. sounds like you're not positive what your motor/ecu from what you said about the company....
 
I should have explained more. I do have an actual JDM B18C with the correct auto transmission. Or so I was told. It came with the wiring harness and ecu. My problem has been trying to connect the engine wiring harness to the vehicle. I have managed to find power wires and ground wires, but I am strugling with the other stuff. I don't know if the Auto portion of the ecu needs to be powered independantly. I also have a pulsing RPM at part throttle.
 
How would I find out what year of engine and transmission I have? There seems to be some mixed information on the P72-901 ECU
 
Could anyone show me a web site or some kind of document on that ECU. Any one that I talk to says ( Oh you have that dreaded ECU ) I mainly need to fing the pinouts for this ECU. I have tried to use other pinouts to get close, but the only thing that any other ECU pinout has in common are the injector wires and the power and ground wires on plug A. pretty much nothing else matches as far as color codes go.
 
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Does anyone know of someone with automatic transmission knowledge that I could contact? I just need a little push in the right direction!
 
Honestly I don't know how much help we're going to be. This isn't a topic that comes up much around here. I'm not trying to discourage you in any way, just letting you know...

There was a guy a while back who did an automatic GS-R into an EK hatch and posted about it on here. Maybe do some searching and see if you can find that thread and get in contact with him?
 
I am a lot closer, but still only have 2nd and 4th gear on the transmission! I have found that the two lock up solenoids on the transmission aren't wired up! I would assume that they need to go to the control unit, but I don't know for sure since the look like they would go in the direction of the harness that feeds to the dash board? Should I just abandon the JDM harness and ecu and find one from a 94-95 Teg GS or LS? This is going in a 98 civic so I could also go with an OBD IIa if that would be better! I don't need anything that needs to be tuned or anything like that. This is used to haul kids and groceries, not to run on the track! Does anyone have a harness and ecu that I could buy? Thanks for all of those that have posted to this, it has me a little bit frazzled!
 
wish i could help , did a gsr auto swap a few years ago , but basically did a body swap just moved everything from one car to the other ,
 
I'm confused... Why are you using the JDM harness? By rule of thumb, you use the harness that came with the car, not the motor you're swapping in. Is it different when doing an auto swap?

I say use the stock harness and add the wires for vtec, knock, and secondary butterfly like you would do if it was a 5 speed swap...
 
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