i just purchased an '89 Crx Si i've done swaps and rebuilds and all that before, i'm not bad with wiring...but i'm not exactly understanding this whole deal.

i've got a '94 b18b1 bottom end (w/ctr pistons)
'92 Ls head(stage 1 crower cams not installed yet)
stock Pr4 ecu (until i get it tuned)

from what i understand the Pm6 ecu is obd0 and the Pr4 ecu is obd0 also but why is it the Pr4 won't directly plug in? and what exact jumper harness am i needing?

i do have the engine harness from my '92 Da and the harness from the '89 Crx what modifications need to be done?

note* I HAVE searched but don't completely understand so please no bashing on me, just fill me in on info/direct me to the right spot, or dont post at all.

-Terrance

'89 CRX cabin ecu plugs


'89 CRX ecu (Pm6)




'92 Integra cabin ecu plugs


'92 integra Ecu (pr4)




sorry for the big picutes, there just quick cell phone pics.

 

stay with the pm6 and just get a base map

 

its not hooking up to your cabin harness because the pr4 you have is an obd1 version. 90-91 pr4 is obd0, 92-93 is obd1.

 

oh ok, i thought the obd1 ecu was p75....

i'm wanting to keep the pr4 because i'm not going to be getting a tune until my motor is broken in.

so until the motor is broken in, the crower cams won't be installed nor will i be getting a tune.

 

it only takes like 500 to 1k miles to break a motor in properly. what you have is fine

 

ecu should plug right in unless you have a obd1 pr4 ecu. mines plugs right in. obd 0 should have 3 plugs. obd 1 only have 2 plugs. check your ecu and plugs.

 

the pm6 ecu has three plugs, just like the pr4, but it doesn't directly plug in...

 

i'm just trying to be safe at this point, i'm in my last year of high school and have a min. wage job. i blew the motor up once already with it not having a tune and still running regular gas(which i totally forgot about me having to use 93 octane.)

and in the mean time i can save for my tune as well

 

i guest i know idea why. mine plugs in. i guest time to use the pm6 or buy another ecu. pm6 is going to run leaner though.

 

any pics will help all of us out. ecu and plugs.

 

alright, give me just a few min. and i'll post some up for everyone.

 

this isn't rocket science. you have an obd1 pr4 instead of an obd0 unit. from 94-95 the ecu was an obd1 p75. it remained p75 from 96+ and it was obd2 for those years.

ninja edit: obd0 ecu's do have 3 plugs, but 2 seperate colored areas on the ecu.

 

your right it isn't rocket science for people it is explained to, now that you had explained it i understand...


then i guess my cabin harness on my '89 Crx si is obd1 because both the harness and ecu have 3 seperate plugs

 

pics posted

 

anyone know anything? or can possibly lead me the right direction?

 

your ecu is obd1 like stated before. get a obd0 one

 

that's my bad. i meant to say that on the ecu jumper there would be 2 seperate plugs for the obd0 cabin harness to plug in, but on the harness itself there will be 3 seperate plugs (as seen in your picture).

the problem is you have an obd1 ecu there, and your stock harness will not plug into it without the proper jumper harness. so either get that harness or get an obd0 pr4.

 

wouldn't an obd0 to obd1 jumper harness be straight...considering obd1 ecu's have more of an advantage for tuning...?

 

either way will be fine, but its easier to chip and tune on an obd1

 

they certainly do. if you ever have an intention on tuning the thing then converting to obd1 would be the best route to go.

 

sweet, so then i'll just get an obd0 to obd1 jumper harness and go from there...

http://rywire.com/store/obd0-obd1-co...3bbed215083122
would just like to make sure its the right product...^^^^^

 

yup that works

 

thats whats up, i appreciate it! when i get things together i'll post up a build thread.

 

sounds like a plan.

don't forget you'll also need a 4-wire o2 sensor when you convert

 

whats needing to be done with the stock crx engine harness? do i still need the da engine harness?