Ok I've looked everywhere and know that no one has the pin-outs to a p-14 ecu models 92-95 Honda prelude si sporting the h23a1 engine with a auto transmission. so here it is what kind of mods are out there that can be done to this ecu? is there any without knowing the real true pin-outs of the dreaded p-14 ecu? reason why i ask is i am doing a fuel system upgrade consisting of fuel cell, aeromotive a1000 fuel pump, 1000cc injector dynamics, aeromotive fuel regulator, sst braided feul lines, aem fuel rail. also i will be adding a turbo kit consisting of a turbonetics t3/t4 turbo, intercooler, wastegate (7-15psi), ect... i have a apex'i s-afc2 as of right now installed. will it handle the mods? i assume i willl have to rip it out and do a stand alone system but then again we run into the pinout problems with the p-14 ecu. anyone got any answers to this?

 

get rid of p14, safc and buy an ECU which can be tuned. lots of them around. its not expensive nowadays.

 

You can't tune the p14 ecu. You'll have to get a p28, p72, or another ecu that can be tuned. Here's a good site to purchase a chipped ecu for your needs:

http://www.phearable.net/

 

Is there any company's out there that make a good stand alone management system that accepts my old 4 socket Ecu harness? Has anyone actually done this same setup before that can tell me exact Ecu swap and what other electronics they used to do it? If I swap the computer out for another I think I'm going to have a problem with the auto trans shift points, or maybe no points at all due to the p28 only having 3 sockets. And the p-72 is a v-tec ecu. Mine is a non v-tec p-14 ecu. Does the stand alone models on the market do away with the factory Ecu all together or do they just piggyback? Point me in the right direction because I'm still kinda stuck. Thanks for all the help so far!

 

Send an e-mail to phearable.net, I'm sure they can help you since a boosted H23a1 is a very common thing, just don't expect that auto trans to last with the added power.

 

I went ahead and sent them a email. I thought it was a common application to do this car also so if anyone has this setup i would really like to know how they did it? What electronics they used? And yea Im going to have to baby this transmision some but overall has been excellent all motor transmission. Ive shown it no mercy to it so far, And it bangs gears hard like the day i bought it. Ill have deal with that if it pops and swap for a manual then. But yea any setups that are out there would be a great help or any general knowledge about this work is greatly appreciated! Thanks again

 

not much you can do with an auto trans. you should find a tuner to talk with that can do it for you. finding someone on the internet 500 miles away from where you live really wont help you unless you are willing to travel there. most people have their own way about doing things, and your local people might have no experience with what they can sell you.

 

The ecu doesn't have to be for a non vtec. It just has to be able to be chipped.

Not sure about the auto trans. situation. Never have dealt with one. Sorry.

 

Yes this is a big problem because there no one in my area that works or know much anything on these cars. I have learned everything I know by reading and working on the car. The thing that really sux if i put the car in limp mode then its on me to fix my screwups. The link above was a Hugh help to phearable.net. these guys know what is goin on! We are working on a fix now and as soon as I pick out the correct parts ill let everyone know if it really works or not....... I am still interested in if anyone has this electronics setup yet, also I am in the process of quickie reverse engineering a color code and pin out for the 92-95 P-14 ecu. If I get them all correct ill post the pin outs for everyone to see. Thanks again everybody!

 

Pinouts for P14 are the same as other Honda OBD1 ecu's (eg P28, P06, etc) and are plug-and-play as long as the one you are plugging in is tuneable. The way I went with my h23a1 is Neptune RTP and Moates Demon. Also, add a Wide Band O2 sensor with wiring to the ecu to be able to read/log O2 readings from Neptune software. Go read over there ALOT before doing anything, there is quite a lot to understand how these ecus function. Also go to http://wikitest.pgmfi.org/twiki/bin/...ibrary/WebHome to learn about the pgmfi system (thats Honda's ecu system). pgmfi.org is the associated forum, but a word of warning, most people over there don't have much patience for Newbs, but read, read, read!
GL
Mike

 

thanks for the setup info, i am going to do some more studying on the subject since we still have not come to a fix on the p-14. i am in the works now of confirming weather or not it is tunable. i know everyone says its not, but there is a aem/fic out there that just might make it tunable. ill keep everyone informed weather it will work or not. also i believe that all odb1 pin-outs are the same except the color codes are different (p14) and a few of the wires in other computers (p28,p72,ect..) pins are placed almost the same just a few switched pin places to accommodate the v-tec and auto trans so due to this some pins are moved and placed slightly different places. i wish i knew for sure that i could just plug and play another ecu but ive not found someone who has swapped the p14 and plug and play another ecu in its place yet. mherkamp was your h23a1 a auto transmission with a p14 ecu? does the 1993 h23a1 use a mag or hall pickup? thanks again!

 

Well it WAS an auto, and then I did a 5spd swap and converted the p14 to a manual trans, then I went to Neptune so I could run e85 effectively. The ONLY change needed to run a civic/integra ecu on a prelude with neptune is "Please take note that the O2 Heater Pin (A6) and EGR Pin (A11) should be switched when running a Civic/Integra ECU." as per the neptune site. If you want exact pinouts for different hondas, I have them, pm me ur email address and I'll send it to you.
Mike

 

OP you've got email.
Mike

 

OK so I've found at least one solution to this problem. I'm sure there is other companys with similar products but most popular is going to be a aem f/ic piggy-back module and also you will need a aem wide-band o2 sensor. This actually makes the p-14 ecu "tunable"! I suggest getting a ecu wiring extension harness, this makes the wiring a much more simple and easy to perform the connections and you are not cutting up you factory harness. You will need a odb1 extension, the extension will be missing the "c" socket, its okay, just jump that straight into the ecu, there is not need to cut any wires in the "c" socket, they control the auto transmission functions. Thanks to mike I'm going to put together a nice exact pin out of the p-14 and all pins that the aem f/ic connects to. If anyone knows I would like to know what the cam sensor signal would be? Is it accualy referred to as "top dead center signal" or " cylinder position signal"? Also weather the cam and crank sensors are mag or hall style sensors? Thanks again mike, its funny I was putting together a color diagram and you confirmed my configuration with matching colors and voltages.

 

Aeromotive a1000 is total overkill. I would not drive on that pump for long periods really of time. They get really hot and are prone to fail with a lot of heat build up.

 

Read this before you decide. I'm not going to tell you what to do, but I feel you should have all the info before you run a piggy-back.

http://wikitest.pgmfi.org/twiki/bin/...PiggybacksSuck
Mike

 

I understand that that the f/ic has some down falls but dealing with the auto transmission is hard to get around with out a few minor problems. Point being that is is possible to manipulate the p14 ecu into a useable ecu in a boosted application is a big step. If I was to change out the ecu now I have problems with shift points, and this is a big problem. So even though the f/ic has a few setbacks, i feel there is less of a setback with the f/ic, sure it might take a lil more tuning to achieve desired performance. And just so everyone knows the a full stand alone ems is not a option on the auto. So to boost a automatic using a p14 ecu a f/ic seems to me the only way to go. Anyone know what that cam sensor signal is called in the ecu pin outs, Is it the cylinder position signal or top dead center signal, or neither?

 

So i now have the aem fic hooked up and running the car. The fuel system is complete. I decided on a walbro 255lph piggy backed to my stock pump. Sst braided lines and fuel lab regulator & filter. I also added a aem high flow rail along with 1000cc injector dynamics injectors. I ordered and received but not installed yet the turbo and a 3 core civic mishimoto rad, oil cooler, trans cooler and OBX ram horn header. I wanted log data before boost hoping to make it easier to tune. Now my tuner tells me that he will not work with a aem fic due to tuning issues. Man I am in a jam now. I spent big $ and alota time wiring and countless hours garage tuning, I was feeling good having a non boosted engine with a mild build running half decent. This is the only tuner I can trust to tune around me and i am 4 hours from him. Any ideas on what I should do? I live in pa, and was going to goto Evans tuning. I am just super bummed right now and not sure if I should switch everything out or put the goodies on and test my Tuning skills to the fullest. I know Hondata does not support a s300 upgrade, I know the p-14 ecu is damned to never being tuned without fic. Hey mherkamp just wondering what ecu where personally running on your h23a1 auto trans? Also Neptune and demon in one package or two separate pieces? I would really like to use the fic if anyways possible.

 

Always ran the stock P14 when I had an automatic, didn't change over to Neptune till after I did my 5spd swap. If you are going to boost, you are going to fry your torque converter and the clutch bands inside your automatic. Do yourself a favor and do the 5spd swap with a stage 2 or 3 clutch kit and then run whatever tuning solution you want. Also, the Demon is the hardware and Neptune is the software, so its 2 pieces to buy. You will also want a wide-band O2 sensor. I know its a lot and its pricey, but thats just the tip of the iceberg for a boosted setup.
GL
Mike

 

I got a wideband O2 (aem AFR gage). I think i will do just what you did. What ecu did u personaly switch to after the 5spd swap? And what 5spd did you use that bolts right up on the h23a1? Thanks buddy you have been so much help!

 

should have talked to your tuner FIRST.

taking him the biggest baddest latest EMS isnt gonna do squat for you if your tuner doesnt use it, know it, like it....etc

 

Yea I just said the same thing right before seen this post
Step one is contact the tuner shop you intend to use and see what they have had the most success with. But in all I've noticed something today, a light turned on. My main problem with the fic on odb1 is the inability to monitor long and short term fuel trims. Problem solved, hack manually Into the stock o2 sensor, using a oscilloscope. I am installing a connection on the side of the center console for a easy tap point to o2 sensor. U need a wide band O2 like a aem Afr gage. Chart voltage output to rpm by running the car thru rpm range. Now you got all you need to make the ecu happy in the o2 map. All you gotta do is tune the fuel map for your desired AFR. Under a load during boost u may need more fuel than you did during the no load condition so just add fuel to whatever areas you want and make sure to go back to th o2 map and adjust. You can cut the tuner shop out all together if all you need is a conservative street tune. If you bring a tuner shop a car that is running really good, then I can't see them not wanting to tweak it in for the track. Oh and .5 volt = 14.7 afr on a narrow band so always tune the o2 map to 14.7 by holding .5 volt on your scope, compensate to hold this by using the chart you made earlier.

 

You can cut the tuner out if you know what you are doing. There is more to ems systems than tuning the fuel to what "you" want.

 

right on yea you really have to understand what the ecu is doing in full depth then that enables you to tune to your desired AFRs, that is really not saying that the car still cant make more power, the dyno can find any dips in the HP an TQ curves and then the tuner tunes those spots out, thus making a nice smooth curve. its up you but if you (yourself) really want to build a car, it seems you better now a ecu inside and out and understand the sensors and there exact functions! tune-ability is all made possible by monitoring the o2 signal thru the hack. all narrowband o2 sensors ive found output .45 volt being equal to 14.7AFR, meaning .45 volts is 0 on long term fuel trim, tune o2 map to output .45 volt to ecu all the time. this allows closed loop operation, and a happy stock ecu. guys with a stock p-14 had no choices but maybe swapping the ecu before the aem fic. swapping ecu means messed up shift points in the auto trans. hondata does not support a s300 for the p-14, neptune does not, greedy does not, i know this as for a fact. the hack is performed by cutting and splicing off the o2 signal to a switch then out of the switch i put a Y, one side to a connector (tap point on side of console) other side going back to the o2 signal you cut. now you have a tap point to connect test equipment to. the switch i thru in there for open and close loop operation because for some reason the aem software does not have the feature. this hack can be done to any ecu for that matter, when you cant monitor the short and long term fuel trims. without being able to monitor fuel trims the ecu and fic will not sync making closed loop untuneable. damn you love me, dont yins!

 

the p14 ecu does not actually control your transmission....thats the job of the transmission computer.