What is involved in converting an OBD1 car to an OBD2?
My motor (b18a1)is OBD1 but the car has an OBD2 ECU. The car STILL isn't right. It's running really rich, and getting BAD gas mileage. I'm about done spending money on figuring out why it's doing this. I don't want to buy an ECU and that not solve the problem.
Thanks!

 

Whats involved in converting is the dizzy,alternator,injectors and ecu.

The problem is OBD2 cars look for more sensors and such.
Do you have a CEL?

 

Only a #6, coolant temp sensor.
I changed it and I'm still getting the code.
What if someone before me didn't do everything to convert it, would it cause it to use gas like it is?
I filled up the car, drove 59 miles and it was at a half tank!
How do I know if it has an OBD2 dizzy?

 

OBD1 ecu (+jumper if your are a 96+ civic) and problem is solved, in running terms. Inspection and state legality issues are another problem to that tho. Your from Florida, so i dont think you have state inspection or emmission requirments.

 

It's a '93 Civic Hatch and yeah, we don't have inspections.
So, I should be able to get an ECU for an OBD1 and it'll fix the problem?
How do I check to see if the other OBD1 to OBD2 stuff has been done?
If it still has OBD1 dizzy, etc and an OBD2 ECU, would it run like this?
What if it has the OBD2 dizzy, etc?
This is my fist Honda and I am completely Honda illererate!

 

to run an obd2 ecu in a obd1 car, you are looking to need a CKF, secondary o2, and thats all i can think of right now.

your car is obd1. get the correct ecu for it. be glad it is an obd1 car. you dont need to convert anything. either get a p30, (del sol vtec, jdm sirII) or obd1 p72 94-5 gsr.

worst case, get a p28 or p06 and have them setup for the b16. the p28 needs no vtec components installed. the p06( with hondata can switch vtec over with a relay and no internals, or be set up to run vtec) will run the car but no vtec.

 

I don't want to convert it. I think it might have been done or some of it has. I just want the damn thing to run right!
How can I tell if the dizzy is OBD1 or OBD2?
If everything is OBD1 except the ECU, I'll get and OBD1 ECU. I don't want to put much more into it, I'm about ready to sell it all...

THANKS!

 

BUMP>>>>>>>>>>>&g t;>.

 

obd1 and 2 dizzys will run on each others. obd0 dizzys get stupid with obd1 ecu's/

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JONESER &raquo;</TD></TR><TR><TD CLASS="quote">I just want the damn thing to run right!</TD></TR></TABLE>

get a chipped p28 or a p30

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dickies_n_FlipFlops &raquo;</TD></TR><TR><TD CLASS="quote">Whats involved in converting is the dizzy,alternator,injectors and ecu.

The problem is OBD2 cars look for more sensors and such.
Do you have a CEL?</TD></TR></TABLE>



don't listen to this guy

The only major differences you'll find between an OBDI and OBDII car are the following

OBDII car has:

an obdII ECU
a knock sensor
different plugs where the harness plugs into the ECU

The dizzy is the same...the injectors are the same...

He is right about the OBDII ECU looking for the knock sensor. However if your running an OBDI ecu it won't be looking for a knock sensor.

 

Maybe its just me.... but the most obvious solution is to junk the obd2 ecu, and find an obd1 p75.

 

It has a P75. Looking in the FAQ on this site, there's a rundown of ECU's and what cars they were in. According to that, a P75 came in 96-00 OBD2 Integras. The OBD1 is a P74/75 that came in 92-95 Integras.

 

Get the OBD1 ecu for you car/motor, whether it's P74 or P75, and call it a day.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dohcdelsol93 &raquo;</TD></TR><TR><TD CLASS="quote">
The dizzy is the same...the injectors are the same...

He is right about the OBDII ECU looking for the knock sensor. However if your running an OBDI ecu it won't be looking for a knock sensor.

</TD></TR></TABLE>

You are correct about the dizzy wires are color for color and the dizzy's are identical other than the plugs. And the injectors are also the same as far as d or b series goes. obd1 and obd2 injectors are the same impedence and flow rate just different style plugs.

You are wrong about a obd2 p75 looking for a knock sensor.

Main difference is OBD2 computers have better proccessors and can "think" faster. I run a jdm ctr computer in my ek hatch and it'll run better any day than a obd1 computer. OBD2 computers do look for a ckf (crankshaft fluctuation sensor) located on the oil pump of obd2 engines. There is and easy fix for that though you can find it on ff-squad.com and it works i've done it many times. jdm obd2 ecu's don't look for this sensor.

But to put it the best way stick with the obd system that was intended for your year car. You need a obd1 p75 ecu or even a p06 will work just fine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SirRevvs &raquo;</TD></TR><TR><TD CLASS="quote">

You are correct about the dizzy wires are color for color and the dizzy's are identical other than the plugs. And the injectors are also the same as far as d or b series goes. obd1 and obd2 injectors are the same impedence and flow rate just different style plugs.

You are wrong about a obd2 p75 looking for a knock sensor.

Main difference is OBD2 computers have better proccessors and can "think" faster. I run a jdm ctr computer in my ek hatch and it'll run better any day than a obd1 computer. OBD2 computers do look for a ckf (crankshaft fluctuation sensor) located on the oil pump of obd2 engines. There is and easy fix for that though you can find it on ff-squad.com and it works i've done it many times. jdm obd2 ecu's don't look for this sensor.

But to put it the best way stick with the obd ECU that was intended for your engine. You need a obd1 p75 ecu or even a p06 will work just fine.</TD></TR></TABLE>

corrected!

what's wrong with an obdI p74???

further more a p06 will run an OBDI B18A/B but it will run like poop. It's Like runing a b16 on a p28. It will have no power and run lean

together we have the power to suppliment for each others short comings!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dohcdelsol93 &raquo;</TD></TR><TR><TD CLASS="quote">

corrected!

what's wrong with an obdI p74???

</TD></TR></TABLE>

I don't even remember what a p74 comes in you shoulda said pr4 then you would've really corrected me. It's cool g.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dohcdelsol93 &raquo;</TD></TR><TR><TD CLASS="quote">
together we have the power to suppliment for each others short comings!</TD></TR></TABLE>

hahaha

 

Thanks guys! So..... I just need to find a OBD1 p74 or OBD p75 and it should solve my running rich and SHITTY gas mileage?
I'll learn someday....

 

obd1 pr4 from a 92-93 integra or obd1 p75 from a 94-95 integra

 

COOL, THANKS!

 

p74 came in the 94-95 Integra.

Just be sure that if you get p75 that it's not OBDII

also be sure that it's a manual ECU, I'm guessing you have a manual tranny.

 

How do I know if a p75 is OBD1 or OBD2? It has a p75 now...

Yes, I have a manual...

 

obd1= 3 plugs 2 rows of pins each
obd2 a and b = 3(or 4 if an auto) plugs with 3 rows of pins


top to bottom:
obd2b
obd2a
obd1
obd0

 

just get a pr4 and be done with it ^_^

 

lots of guys are selling them on this thread

https://honda-tech.com/zerothread?id=2110916

just check vouches for them before sending $$$

You might be able to pick them up cheaper at a local junk yard. The one I go to sells ECU's for 50 bucks.

Just ask them if they have any 92-95 integras. Chances are if they are in a junk yard they are LS/GS models anyway. Double check by the code on the ECU, if still in doubt check the code on the engine and the plugs on the ecu. So long as it's 5spd the ecu will work for you whether its p74-p75-pr4