Solving H22A Stumbling

[Losiracer2]

also, i would just take your P13 and remove the cover and see if you see any burnt resistors or connections. Sometimes that can be the cause of some issues. Its just a couple phillips head screws for the cover.

[CB7Man]

If you have a JDM ecu, your going to have a burnt section, kinda looks like this.


Doesnt effect the rest of the ECU.
Its the IAB circuit, the butterfly valves that open at 4,500 rpms
JDM engines have a bad "black box" it just burns out that part of the ECU
I blew up the one on my USDM ecu, repaired it from a spare on JDM board, but I replaced the "black box" with one from a F22A6.

As for your coil swap, you probally had the dizzy cam alignment 180 off. (yes its possible, I did it, ask ddcb7 )
His car didn't start when we did that, and we converted from external to internal

Actually to tell you the truth, the knock sensor is designed to sense knock in the 2000-3500 area.
If your knock sensor wiring is not shielded enough or if you have a genuine detonation going on at that RPM, the engine will pull timing.
I had this problem.

You can unplug the knock sensor and try that too.
The knock sensor is activated at 2250 rpms, as in your CEL will come on if you hold that with it unplugged. The knock sensor is greatly affected by interfearance, so if your wiring isnt perfect, youll have problems.
With the KS unplugged the engine will pour fuel, but it boy it PULLS

Just to make sure, your running (Premium) 93 octane right?
91 wont really cut it, the engine really needs 95 if its JDM, but 93 is availabe in some parts of America.

Also winter fuels (ethanol mix) will make your car run like crap too.
I took a trip to Oregon, fueled up and it ran like CRAP, no power at all.
Barely making it up hills.
I came back and pumps read "Fuel contains atmost 5% Ethanol"

Wierd Cali used to have 93 Octane, I remember my mother didnt want to put Premium in the old 7 series, wanted to save some money. She put regular in it. Came home and it sounded like someone was hammering away at the engine block
But I think that was before knock sensors

[WagonLX]

I will try that conversion tomorrow, right now Im trying to work out some of the basics. So-I pulled the computer and all is well, now Im trying to figure out exactly how the wiring should be hooked up. VTEC solenoid-Green/Yellow-Pin A4. VTEC pressure switch-Light Blue-Pin D6, but mine has no pressure switch so it is wired into A4 also to enable VTEC. Ground-Black/Red, I dont remember hooking this wire up as it was a long time ago{where is this wire?}. Intake Air Breather-Pink-Pin A17. 12 Volt-Black/Yellow-where exactly do you have this wire hooked up? Knock Sensor-Red/Blue-D3. I have the 12 volt-black/yellow wire hooked up to another black/yellow wire near the computer, as I thought all black/yellow wires were 12 volt. please correct me if I am wrong. Also, I live in a 91 octane state and thats the highest rating I have found here. Does the octane rating really make that much of a difference? The knock sensor issue-feels exactly like what I am experiencing-retards timing, and I will really check this one out.

[WagonLX]

Ive answered my own questions about the wiring. The Black/Red is ground for the VTEC pressure switch which I dont have, and I tested my Black/Yellow for 12 volts. The knock sensor is definitely a culprit for me and Ill test it out tomorrow as this does affect timing if it sees a fault. Would'nt that set a CEL though? The octane rating has always been questionable to me also.

[WagonLX]

So I converted to external coil a couple of days ago and all is working well, so far. Thanks ZigenballZ for the link, it really helped. I have not felt the stumbling again, yet. Every time I do something I try to make it a habit to reset ECU and then do a relearn procedure. Then I dont feel stumbling for a few days later, after computer parameters have been set. Correct me please if I am wrong on this one. Thanks for all the input, as it has really opened my mind to the possibilities of what is really going on!.

Has anyone ever heard of or made a knock sensor light for testing?

[cb7trancebeast]

so your problem was internal coil and all u did was convert to external?

[WagonLX]

Yeah, so far, so good. I am going to give it a week before I call it good though. I will repost with results.

[cb7trancebeast]

nice i have the same problem

[10k]

ok i have something to ask you do you have the map sensor on top of the tb wired up? cause i had mine wired up at first and it bogged and it..was stumbling too but once i went back to the one our cars came with it runs good..

[WagonLX]

Its been awhile now, and problem is back. I do have the map on top of the manifold wired in, but I had the black box map wired in before, thinking that this was the problem but it made no difference. Ill try going back to the one on my car as I have an extra one that I can try also. I would really like to test the knock sensor also. Im trying to make a test light running into the car, to make it light up if it sees a signal from knock. Thanks again for the help. I wish I had another computer to try also. I need a little monkey to sit under the hood while I drive!

[10k]

haha yea..so far my was doing the exact same thing and i did the conversion methed but from external to internal and its way different from how it was driving

[WagonLX]

KNOCK SENSOR!! But CB7Man, you already knew this. Thanks for all the help and support, it was veeeeeery appreciated. Thinking about going P28 and just eliminating this little bug.

[WagonLX]

This is a huge question for all the JDM H22 guys. Are you running P28 or P72 ECU's? If so, did you have hesitation, stumbling, or miss issues with a P13 ECU? The thing Im trying to get at is it seems to me that the stock P13 ECU's from Japan have an overly sensitive knock sensor signal. The only thing I can think of that would cause this would be the higher octane rating of fuels. But with RON ratings in Japan and AKI ratings in the US, they should be comparable. Unless, you live in a state like I do with only 91 octane being the highest. Hit me back on this one, as I need someones reply that does not live in a beautiful higher octane rating state on the ECU.