How hard is it to find ECU for F23A4 5speed

[Geewiz]

How am I full of sh*t? I thought we were "friends" lol.

Also, F23A4 uses a different wiring harness for ULEV. The exhaust manifold and exhaust shield are different (obviously) and a wideband primary 02 sensor (more expensive than LEV). The catalytic converter on the A4 is the same as F23-F23A1, the EGR valve is the same as F23-F23A1 and the 2nd primary 02 sensor on the cat is also the same as the F23-F23A1. The internals on the A4 motor are the same as the A1, just a different valve cover. The ECU on the A4 is tuned for strict cali emissions. Everything above also applies for SULEV as well.

Here's the thing, you can't just "SWITCH" the exhaust manifold, O2 sensor, and ECU, because the wiring harness on the A4 motor is ULEV and not LEV which means the pins will be different wired to the ULEV ECU and it won't read LEV components correctly unless you modify the pins and find out which wire you need to go where to the ECU. Or you can go to a junkyard and do what I did, swap the engine bay wiring harness's X2 (driver side harness can stay the same), dash wiring harness's X2, ecu, ignition switch, ignition and multiplexers (depending if the harness is from an EX to an LX, you will need blue multiplexers). Believe me, I tried using the 00 ULEV ECU with my F23A motor, and it ran like caca. Lastly, remember that 98-99 use a temperature sensor on the side of the block that shows you the cars reading, where 00-02 use electronic ECU readings. 01-02 uses a bit newer technology within the ECU than the 00. I'm 99% sure you can't use components from a 00 in a 01-02. And lastly, yes I wasn't sure about the 01-02 not being able to use OBD1 in cali, I heard it from someone but It never concerned me since I'm 98.

A lot of good info. What I did is I ended up getting rid of the ULEV manifold, and stock cat converter, and got headers, hi flow cat, and Magnaflow catback. I kept the stock ULEV wideband O2 sensor. I figured more accurate, why not? (32 bit vs 16 bit.) CEL was on for bad emissions obviously, so got a defouler and extended the second (post cat) sensor out like and inch and tada. This was while I was an auto still and the car's get up was just a little better (basic bolt ons, not much to expect) but not worse. The ECU is still maintaining my fuel ratio since its ULEV wideband sensor to ULEV computer. I know the slight change in back pressure might have some effect but I figured negligible. Should be same once its a manual.

I don't know exactly what I'd do it I turboed because that has been tempting for years, because you want the wideband for tuning but it wouldn't work with an OBD1 chipped P28. I'd have to look at AEM EMS and see how that works. Probably would have to use their UEGO sensor and swap wire harness anyways. And that comes back to OPs problem is I wouldn't want to go OBD1 anyways because of emissions testing here in Ohio.

 

[NASOHC]

Most of you all are full of sh*t.

luciusad2004, there is no F23a4 that is non-ulev.

F23A4 is the ULEV engine.

F23A (JDM) and F23A1 are VTEC non-ULEV. Please read the 6thgenaccord FAQ for more info... *STICKY*?????

- Nikita

A lot of good info...

Ok,


Here's the break down on ECU's based on model year car you need:

98-99 Accord 5sp Manual
99-00 Accord 5 Sp Manual
01-02 Accord 5 Speed Manual

If you interchange any of these into another year, good luck!!! LOL. Just don't do it.

As per Engines:

F23A1 VTEC is Non-Ultra Low Emission Vehicle
F23A4 VTEC Ultra Low Emission Vehicle

Long blocks are identical - harness, sensors etc. may differ which is why you need the right year ECU according to year.


BTW: I have an AEM EMS for Sale if anyone is interested, PM me. Works with all 98-02 Accord BUT only with MANUAL TRANS applications!!!

ENJOY!!!

 

[luciusad2004]

Majestic Honda shows the part number of the ECU for my VIN as 37820-PAA-408. Can anyone verify that this is what i need to be looking for?

 

[Geewiz]

After just coming back from the dealership this morning 2 things I learned. Honda corp. doesn't tell dealer part or mechanic guys anything other than one specific ECU, the last one used for that exact year and trim. Which brings me to the second thing is that there just are varied ECU numbers that work with the same car. It's just that sites like Majestic and Honda part guides are just going to list the last version they made. I just which I knew what the difference was.

So follow NASOHC's guide. If the part number for the ECU comes from a car matching his guide, that should work.