I have a 96 GSR obd2a and looking to swap in an LS Vtec motor that is currently obd1. My plan is to swap over my obd2 dizzy, alternator, injectors, etc. onto the LS/V motor.

While using my original wiring harness, I plan to use an obd2a -> obd1 jumper harness to use an obd1 ecu for tuning purposes and have the motor run as healthy as possible. When it comes to emissions time - I'm going to remove the jumper harness and install my OEM USDM GSR ecu.

Before I swap the motor in, I'll tap the block for knock sensor since it's required for obd2.

Does that cover all my bases? I want it to run reliably but also pass legally when emissions comes around. Thanks.

 

You'll have to do the CKF bypass as well as when you put the OBD2 ECU back in its will look for it. You'll need to leave all your Evap parts hooked up as well for the same reason.

 

Thanks that what i figured. Won't the usdm oil pump already have the cfk sensor? I suppose it will still be there running the obd1 ecu - will that throw a code?

I guess in the end, all I care about is no cel at emissions time with the obd2 GSR ecu:

 

Isn't there a ecu harness snip trick that makes an obd2 ecu think that it sees the cfk?
So your obd1 engine and obd2 ecu work together with no cel at emissions.
I'll never be able to find the instructions, but somebody else has heard of it.

It's referred to in this link:

http://www.nonvtec.com/forums/b18b1-...oto-t4218.html

 

I thought the whole Cfk issue thing was for JDM motors since they don't have them? This is a USDM b18b block with USDM oil pump that I'm looking to get. The motor is currently obd1 but i plan to convert it to obd2 With my original dizzy, alternator, and fuel injectors.

Basically, I want to run an obd2 LS Vtec with a jumper harness to run an obd1 ecu for tuning purposes (and run with it everyday until inspection day). At the same time, when emissions comes, I want to be able to pop in my original obd2 GSR ecu and pass with flying colors.

 

The obd1 will not be looking for a cfk sensor, let alone i dont think its even hooked into the ecu after the jumper harness. It will not put out a code.

If the motor is obd1 it will not have the cfk sensor (i am pretty sure here.). Unless you do convert the oil pump to obd2.
I know my obd1 original integra motor had no cfk sensor.

Heres the link to bypass the cfk sensor on obd2 ecu if you do not want to deal with it.
.:FFS TechNet:. » ECU & WIRING How-To Articles » CKF Bypass Trick

Just swap electrical components to your knew enigne. (Sensors.)
Bypass the cfk on the odb2 ecu.
Tune the obd1 ecu and just swap for inspection.
Unless the guy gets down there to look for the crk, you will be fine bypassing it for obd2 and plugging back in the odbd1.

 

If it's a true OBD1 engine it won't have the CKF by the crank so you'll have to bypass for when you use the OBD2 ECU.

 

There it is, the link that I couldn't find.

If you want to spend $450 and swap out parts, here's the list from the above thread/link that I posted:




He offered to splice/cut some wires on my ECU, to avoid any CFK/P1337 engine codes.

I didn't know which helpful check engine warnings (codes) I might not get in the future, if I let him splice and cut some wires on my ECU harness.
He did not cut any wires.

He took the original engine B18B1 out of my 2000LS and these are the parts, from my USDM B18B1, which were needed to get rid of the CKF (P1337) code.

oil pump 15100-p72-a01

oil pump pick-up strainer gasket 15221-pw0-s01 .......(I bought a new one)

oil pan gasket 11251-p30-004 ................................(I bought a new one)

tdc sensor 37500-p72-a01

timing belt stopper plate 14535-p72-a00

stay for tdc senser cable 32756-p72-a00

timing drive pulley gear 13621-p72-a01

key for timing drive pulley gear 90704-634-000

o-ring 91308-p3r-t01 .........................................(I bought a new one)

lower timing belt cover 11810-p72-a00 (needed to fit over the usdm oil pump)

timing belt cover bolt 90007-679-000 (civic only uses 2 bolts)

 

Awesome, thanks for all the info and help everyone, I'll update this thread once the motor gets dropped in.

 

This isn't very helpful but all I used to pass was a 94-97 LS ecu and the o2 sensors plugged in. This was in a 97 civic DX though.

 

Did you have a knock sensor?

 

No. I believe that is why the 94-97 LS ecu is used because it checks the least amount of monitors and excludes the knock sensor because b18a-b did not come with one. I apologize if this is misinformation, just trying to help. When I had this swap it was already done by a friend and this is how I passed inspection. Also worked for 98 spec jdm itr swap.

 

Very interesting. It makes sense though. Given obd2 started in 96, is there a way to distinguish 96-97 LS ecu's vs. 94-95?

 

That I'm not sure of. All that I can tell you is that it needed to be obd2a (NOT b) LS 5 speed ecu. 98-01 obd2b ecu would not plug directly into my harness. Again this was for a 97 civic so it could not be the right information pertaining your car. Ran my car with a jumper harness and a chipped p28 after it would get inspected

 

https://hondata.com/index.php?_route...identification

Obd1 ecu has 3 plugs and 2 rows of connectors.
Obd2 ecu has 3 plugs and 3 rows of connectors.

 

To clear it up:

Civic OBD2A 96-98
Civic OBD2B 99-00

Integra OBD2A 96-99
Integra OBD2B 00-01