jorgelm86, according to the factory service manual, a DTC 4 is "a problem with the Crankshaft Position (CKP) sensor circuit."

Since you didn't swap out the ECU, and you kept the old distributor and coil from the F22B2, I don't think the DTC 4 is related to the swap. It may be that you just have failing distributor. Have you cleared the ECU memory to see if the CEL goes away? Do you have a factory service manual to troubleshoot?


Not everyone. No problems running a virgin factory VTEC ECU. Runs strong. Great DD.

 

You can pick up virgin P28's on eBay or the junkyard, and chip it yourself if you're any good with board level soldering. You can pick up the chip kits from Moates.net. Otherwise you can find them already chipped online.

It's OBD1 so as far as wiring it in its a direct swap because the plugs are the same. (I'm assuming you're still OBD1)

As far as tuning it, your best bet would be to find someone around your area that has experience with tuning.

 

That's great to hear! Mine ran great also. I got an average of 34MPG on it.

 

I got an extra 1mpg in city driving going from the old F22B2 to the F23A1; probably because of the milder VTEC lift at lower RPMs. Highway mileage is the same as the F22. 34mpg is awsome. I can hit maybe 31 or 32 driving 65 on the highway but the speed limit in CO & UT is either 75 or 80mph so I tend to get 28mpg at those speeds.

jorgelm86: With a non-VTEC ECU, your car should run fine up to 4000rpm and then run out of breath due to a lack of VTEC. I ran mine for a week or so like that with no problems. To get the VTEC working, you'll need replace your ECU and wire the VTEC solenoid and VTEC oil pressure switch. I think '94/'95 EX (VTEC) used a P0A.

 

Roader i have clear the ecu but the cel keeps coming up im also getting code 43 ... and no i dont have a throuble shoot... ok thanks im going to the junkyard this weeken does the ecu off the ex have to ve stickshift... and i will also need help on how to do the wiring....

 

Monopoly man thanks so much for the advice on the p28 im thinking of doing it but right now im in a buget so im just trying to get the vtech to work

 

DTC 43, not DTC 4? Here's what the FSM says about DTC 43:
The O2 sensor should be fairly straightforward: Is it hooked up? Is the heater circuit open?

Troubleshooting the fuel system is a bit more involved. The DIY sticky has a link to online manuals:

Online Manuals

I can't imagine that this problem is specifically related to the swap, especially since you used the F22 intake manifold. Maybe something got broken or was left unconnected during the engine R&R. Start with the O2 sensor.

ECU: Not positive since it's OBD1, but I think you do need a manual trans ECU. A quick web search showed 37820-P0A-A01 as the part number. Wiring VTEC isn't all that difficult. Cut the harness out of the ECU donor car if they'll let you & be sure to include the solenoid (VTS) & pressure switch (VTP) plugs & pinned ECU plugs when you do. Try to keep the harness in one piece without cutting the VTEC wires. Then just unwrap the tape, remove the plastic wire loom, and extract the intact VTEC wiring harnesses. I just ran both wires separately through the firewall grommet that holds my amp power wire. I think the wiring is D6 (VTP) and A4 (VTS). You should be able to find an OBD1 ECU pinout online to help you identify the plugs & pin locations.

A good how-to on OBD1 ECU plug pin removal:

phearable(dot)net/tech/wiring/obd1pinremoval(dot)jpg

 

i have actually just completed my f23a1 swap in my 94 accord. I just took the intake manifold with everything on it from the f22 and slapped it on, then i put my headers, f22 distributor, f22 ecu, original accord plumbing, wiring, ect. Started right up after fuel pressure built back up, will have to get better plugs and wires, i think the dust got to them lol

 

Let us know how it works out after you get the ignition stuff replaced. Other people need hear how an F23 swap is working in an OBD1 car.

 

Passed first emissions test since swap. All readings grams per mile:

• HC limit: 1.20, HC measured: 0.22
• CO limit: 15.0, CO measured: 2.8
• NOx limit: 2.00, NOx measured: 0.97

HC & CO measured around 20% of the limit but NOx measured about 50%. EGR passages cleaned before the swap, 6500 miles ago.