F23 a1 swap into CB7

[93lxACCura]

1993 CB7 putting an F23 from a 98 Acura CL


I have just finished this swap i got the jumper harness for the ECU and hooked it up. I have spark air and fuel just wont start the car cranks but will not catch.
I am using the original wiring harness from the f23 and the original CB7 harness I had to cut the starter wire connectors and rewire it. I was wondering if anyone had done this that can give me some input.
am i missing something please help.

[FNEG]

f23 harness??? i don't think pins will be in the right places going from the obd1 to obd2 engine harness most honda swaps still use the same harness that came with the car and modify it or add sensors that you need. i am just wondering why did you stay with obd2 and not convert to obd1 it would have been cheaper in the end just need the f22b1 dizzy and a poa ecu and swap pins a6 and a11 and drop the resistor box for the f23 injectors or keep it and use the old injectors. oh yeah do you have the resistor box in because the f23 ones don't need it

[C91BLX7]

Sounds like a major head ache.

[FNEG]

oh yeah i am pretty sure come to think of it that you can't use the f23 harness in that car because for one the iacv is a 3 wire unit not a two like on you car and the wires that go to the dizzy on the old motor have on the sensors in the dizzy and on the f23 it breaks them up and they are located in diffenrt spots down on the crank instead being in the dizzy like on the obd1 units. and like i said the resistor box and the knock sensor on the back the f22ax don't have a knock sensor so needless to say it might work if the pins are in the right places where the harnesses plug into each other but on the body harnes you will be missing wires to components that are cruical for that ecu to work no knock means no vtec no crank angle means nasty cel and f...ed timing as far as the ecu know not that the timing is off or anything. and the iacv won't work right so you will have surging or it will idle fine just stumble at part throttle. and if you have gotten the one type of f23a1 i think it is a ulev or something like that then it is also going to have a 5 wire o2 on it so the body harness will be missing quite a bit of wire and that is if they are in the right spots(which i doubt they are) but i think the wiring is why it won't start

[93lxACCura]

Thanks

I have the dizzy from the f22 on there, I am pretty proficient with fixing cars but the wiring gets me. Should i try to connect the f22 harness to the f23 engine or would that not work i was gonna go through and find each wire and make sure the right ones are connected. If i sound retarded its because i have no idea what to do when it comes to wiring. i did drop the resistor so thats not an issue i have the old ECU from the f22 would that work im not sure what the POA is?

[FNEG]

to get vtec to work with that setup it will be eaisiest to get a obd1 poa ecu out of a 94-95 accord ex with a f22b1 in it and the dizzy from that same make and model as for the harness put your old harness on wire up the o2 to it, the dizzy may not plug right in but the wires color should be the same( keep in mind i did this swap in a civic and i am not famillar with the cb7's wiring) the altenater should plug right in as for the iacv the only thing you can do to keep it is get a 3 to 2 wire adapter plate from blacktrax or make a block off plate and just plug in your old one to it and just adjust the idle at the idle screw on the throttle body.(this is what i did works great) you will have to loop the coolant lines also. and like i said before on the injectors you have to drop the resistor box. the obd2 injectors will work fine but you will have to shave down the tabs on them so your clips will go on them or you can cut your clips off and put on the f23 one in there place so they plug right in. on the harness that plugs into the ecu you will have to swap the wires on pins a6 and a11 some reason the poa is the only ecu honda swaped this on if you don't do this you will get a cel for egr and o2 heater. as for the knock sensor just ignore it because the f22b1 doesn't have one so that ecu will not look for one. as for your egr install the one from your old motor and plug in and any additional sensors that won't plug right in just use the ones of your old motor they will work and they are obd1. the plus side to doing this is that you will be obd1 and you can use a chipped p28 in the future (just swap a6 and a11 back when you do this) i think this is about it just pm me or post if you need more help but like i said as for wire colors i really can't help you there. oh yea if you don't like the iacv problem you can also get a f22b1 intake and use it and the iacv will work then

[FNEG]

does anyone else have any more info for this guy that might know the cb7 wiring better

[93lxACCura]

Thanks

I dropped the CB7 off at a Mech to do the wiring. Thanks again hopefully ill be able to put some info on here soon!

[FNEG]

late response
cool good luck i would hate to pay that bill. but you gotta do what you gotta do

[deevergote]

I've heard MANY nightmare stories about F23A1 swaps... I don't know if we have anyone here with one running correctly... I don't know why.

[FNEG]

I've heard MANY nightmare stories about F23A1 swaps... I don't know if we have anyone here with one running correctly... I don't know why.

i don't either i just think people try to use all the obd2 goodies instead of using obd1 f22b1 goodies on the f23 motor

[deevergote]

Yeah, I'm sure that would work well enough. There are some differences between the two, but they can't be that different.

[joekt]

to get vtec to work with that setup it will be eaisiest to get a obd1 poa ecu out of a 94-95 accord ex with a f22b1 in it and the dizzy from that same make and model as for the harness put your old harness on wire up the o2 to it, the dizzy may not plug right in but the wires color should be the same( keep in mind i did this swap in a civic and i am not famillar with the cb7's wiring) the altenater should plug right in as for the iacv the only thing you can do to keep it is get a 3 to 2 wire adapter plate from blacktrax or make a block off plate and just plug in your old one to it and just adjust the idle at the idle screw on the throttle body.(this is what i did works great) you will have to loop the coolant lines also. and like i said before on the injectors you have to drop the resistor box. the obd2 injectors will work fine but you will have to shave down the tabs on them so your clips will go on them or you can cut your clips off and put on the f23 one in there place so they plug right in. on the harness that plugs into the ecu you will have to swap the wires on pins a6 and a11 some reason the poa is the only ecu honda swaped this on if you don't do this you will get a cel for egr and o2 heater. as for the knock sensor just ignore it because the f22b1 doesn't have one so that ecu will not look for one. as for your egr install the one from your old motor and plug in and any additional sensors that won't plug right in just use the ones of your old motor they will work and they are obd1. the plus side to doing this is that you will be obd1 and you can use a chipped p28 in the future (just swap a6 and a11 back when you do this) i think this is about it just pm me or post if you need more help but like i said as for wire colors i really can't help you there. oh yea if you don't like the iacv problem you can also get a f22b1 intake and use it and the iacv will work then

thank you sir, i have been trying to figure this egr thing out for a while now..


btw deev my f23 runs really well, i have egr unhooked right now so i get a check engine light when im on the freeway but other than that it runs fantastic.

[joekt]

Okay so I got that done but I wanted to make sure and post my fidings, pins a6 and a16 are the ones you want to switch,
A11 is ignition something or other and the car wouldn't even start with those two switched, again though thanks for the information fneg

[FNEG]

for me it was a6 and a11 but my car is a civic not a cb7 but here is a quote that backs up the a6 and a11 pins you might want to check your wiring just because you have no cel doesn't mean it's right number 12

I did a search and was surprised that there was basically zero info related to this swap so I decided to do a write-up while I was at it. I just dropped the motor in over the weekend and here's some info that may help some of you guys. If anyone else out there has this motor too and can add to this thread, go right ahead.



You would think that since this is an F22 and the original engine is also an F22 that it'd be pretty straightforward and be a direct drop in swap......that is far from the truth tho. It basically requires all the same mods as a an H22 swap plus a few other things. It's still not too difficult but I would rate it as slightly more difficult and more involved than an H22 swap. It took me about 17 hrs. to assemble the motor, pull the old one, drop the new one in and have it running. If you plan on doing this swap yourself in your back yard, it may take a few days or even a week or so because you probably won't have quite the assortment of hardcore tools that I have. It is still very do-able on your own.


Install Tips:

intermediate shafts are different - use the 90-93 interm. shaft and axles

I used the 90-93 accord brackets, alternator and P/S pump (A/C has been removed) since I did not have the 94-97 stuff. It required tapping one hole in the block to mount the alt. bracket and cutting off part of the P/S bracket.

The block does not have the cutout for timing marks on flywheel so make sure you use an underdrive pulley with timing marks on it.

Since I'm using the 90-93 accessories (alt. P/S), and the 94-97 u/d pulley, I had to use an H23 P/S pulley. It is smaller and lines up better with the u/d pulley.

The intake manifold is completely different especially the fuel rail and other fuel system parts. I had to do excessive modifications to the fuel rail to get it to work. The fuel lines goes at it from the D. side so I had to move the fuel connection to the P. side of the rail and relocate the fuel pressure regulator to the D. Side. I also had to plug up one additional opening on the fuel rail. The fuel line needed to be bent so that it does not hit the trottle. Again, the manifolds are completely different so sensor/devices are in totally different spots and require some re-wiring to get them to work. Vacuum connections are on the D. side backside of the manifold so I had to run new vacuum lines that reached. I also had to rig the throttle cable (zip-tied in place for now) but I will be making a throttle cable bracket soon.

The front crossmember needs to be cut like crazy to get the header/a-pipe to fit. A huge chunk needs to be cut out to even make room for the exhaust. Also, the a-pipe is only about 1.5' long while the CB7's is about 2' long so the exhaust does not meet up at all. Plus the rear flange on the a-pipe is a two bolt flange while the 4th gen is a 3 bolt. Some pretty excessive exhaust modifications are needed.

You want to use the CB7 trans mount but it reqires either the holes in the trans to be tapped so you can put studs in there, or you can do what I did and weld onto the mount so that it meets up with the existing studs.

You want to use the CB7 D. side mount but it does require some modifications. There are two parts to this mount.....the engine mount and the car mount. The engine mount needs to be cut on one side because it will hit the timing belt (ouch!!) and because the mount is different, the timing belt cover also needs to be modified to to fit it. The car mount part remains unmodified.

Use the Cb7 front and rear mounts and no modifications are needed.


I looked at the wiring diagrams and ECU pinouts for both the 93 EX and 94 EX and there are a few differences. I re-wired the ECU pins and a few things under the hood to match the 94 EX wiring and pinouts. If you wanted to, you could get away with ONLY running the VTEC wires and swapping pins A6 & A11. I went a few steps further and rewired mine to match the 94-95 wiring exactly. You don't have to if you don't want to. Here’s all the wiring the changes:

1.Pin D7 goes to the 3 wire data link connector - Not part of the 4th gens, not needed, and not wired up. I may end up adding this down the road so that I can plug in my scan tool.

2.Pin A10 goes to an Engine Mount Control Solenoid Valve – Not part of the 4th gens and I do not have the valve so it’s not hooked up. This shouldn’t cause any running issues and will not kick on the CEL.

3. Pin A14 goes to the Fuel Injection Air Control Sol. Valve – Also not part of the 4th gens. It’s a two wire solenoid, one wire goes to Pin A14 and the other wire goes to a +12V switched wire (grabbed at the Idle Air Control Valve cause it’s close by).

4. The Intake Air Bypass Sol. Went to Pin A17 on the 4th gen, but goes to Pin A19 on the 5th gen. It is wired up, but the bypass sol. was removed long ago. This should not affect running conditions and will not kick on the CEL.

5. The Idle Air Control Sol. Valve used to go to Pin A19 on the 4th gen but does not exist on the 5th gen. engine and therefore is not wired up. There is an Idle Air Control Valve (not the solenoid) that goes to Pin A9 but it is wired identical to the 4th gen and remains wired that way. These two valves are not the same and not related.

6.Pin A22 was a secondary voltage wire that used to go to the Ignition Control Module (along with Pin A21) but is not used on the 5th gens.

7.Pin A8 was a secondary voltage wire that used to go to the Main Relay (along with Pin A7) but is not used on the 5th gens.

8.Pin D19 used to be a shared sensor wire but now goes directly to the MAP sensor. All previous sensors sharing this wire now go to Pin D20.

9.Pin D21 used to be a shared sensor wire but now goes directly to the MAP sensor. All previous sensors sharing this wire now go to Pin D22

10.Pin D6 is the VTEC press. Switch.

11. Pin A4 is the VTEC sol.

12. Swap pins A6 & A11 at the ECU. A6 is an O2 wire and A11 is an EGR wire. These are opposite on the 5th gen. Swap these pinsor your car will run like shit!

13.Also worth mentioning, but not used on my manual trans - Pins D5 and D14 are new additions that would run to the AT control module.

The F22B1 does not have the Idle Air Bypass Solenoid.

All other ECU pins and wiring are identical for both ECU’s. These are the only changes.


Here's a few pictures to give you more of an idea.



Still haven't wired up VTEC yet. The exhaust is not done yet so I'm not driving it on the street (running an open header right now and it's loud as shit). I'm running the PT3 ECU for now until the exhaust is straight. The P0A will go in sometime this week.



This shows the part of the cross member that needs to be cut to fit the exhaust.



Shows the cut P/S bracket.



Shows my ghetto throttle mount for now. I will be making a custom one soon.



Shows the fuel line bent to avoid hitting the throttle.



Shows the vacuum lines run in back of the manifold.



Shows the piece I welded on to the trans mount.



Shows some mods done to the D. side engine mount.