First: This is nothing bad about Kenji`s ECU`s . I like mine a lot...

The story:
After the weather cooled down and I`ve thrown in my oilcooler, I noticed that the rear of my ITR is black covered from running rich... The right rear light shines darker than the left, even the wing is covered with black particles...

I went back to stock ECU, cleaned the car and the rear is clean now... So it`s just from running rich with that ECU from Kenji.

Two questions:

1) What are the dangers of running that rich all the time ?

2) Anybody elso noticed that ?

I know that Kenji`s ECU should not be driven daily, only racing. Since I knew this, it`s not a big thing for me... But I want to know for peace of mind

 

Do you have a V-AFC or custom ECU setup? You should tune that sucker, it runs quite rich (as you already figured out).

You won't do much harm by running rich all the time, but your gas $$ would cost you a bunch.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 &raquo;</TD></TR><TR><TD CLASS="quote">1) What are the dangers of running that rich all the time ?
</TD></TR></TABLE>carbon build up, poor fuel economy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 &raquo;</TD></TR><TR><TD CLASS="quote">2) Anybody elso noticed that ?</TD></TR></TABLE>not with a Kenji ecu... but the stock ecu is very rich in the upper rpm range.
removing fuel (vafc) made more power and stopped the black stains on the rear bumper.

 

Mugen N1 ECU here and this defines the word "rich"!

Right rear of my CW bumper becomes black even though I wash often. I am still running a high flow cat also. U know your car is running rich when driving on the street when i lift off the throttle it back fires and pops small blue flames out of the exhaust...... Love the ECU on the track though!

 

My old EG ran rich with Kenji ecu,as said above get it tuned it will solve that problem.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 &raquo;</TD></TR><TR><TD CLASS="quote">First: This is nothing bad about Kenji`s ECU`s . I like mine a lot...

The story:
After the weather cooled down and I`ve thrown in my oilcooler, I noticed that the rear of my ITR is black covered from running rich... The right rear light shines darker than the left, even the wing is covered with black particles...

I went back to stock ECU, cleaned the car and the rear is clean now... So it`s just from running rich with that ECU from Kenji.

Two questions:

1) What are the dangers of running that rich all the time ?

2) Anybody elso noticed that ?

I know that Kenji`s ECU should not be driven daily, only racing. Since I knew this, it`s not a big thing for me... But I want to know for peace of mind

</TD></TR></TABLE> 1) not really any danger, except creating a hole in your pocket due to gas costs.

2) I run a mugen spec kenji ecu and my bumper is black as well. I've talked to my tuner and he said with a vafc we could easily lean it out so it would be running at the right mixture. But he also added that the program was excellent. (kenji's mugen program)

 

What exactly is the Kenji Ecu (as in specs)?

 

Mine ran real rich as well...However, Yack took care of that for me

 

Mine ran great all the time.. never had any black bumper ****.

 

running rich can wash the cyliner walls and reduce ring seal.

running rich can clog your cat.

running rich means you aren't making the most power you can.

It isn't as benign as people make it out to be but it is better than detonating.

 

Why do most of the aftermarket ecu`s run rich ?

 

It makes the cars safer (last longer) for the others in the world that don't have as much attention to the cars at we do.
-a bad tank of gas
-putting a tank of low octane fuel in by mistake
-poorly chosen engine modifications

 

I sold my v-AFC. Now I think I want to get another one and a fuel pressure regulator. I won't be going hondata anytime soon.

 

I was curious of this as well. If you running "rich" so to speak that means you are not effectively burning up all of the fuel sprayed into the combustion chamber? So where does this extra fuel go? Either out through your exhaust to eat away at your cat and muffler innards? Down the cylinder walls causing poor ring seal? I have been running very rich for a few months after the JDM ITR 4-1 and Carsound (which fell apart from running rich and is now gutted. to me) install. The Kenji ECU and AFC were just ordered yesturday. Can't wait to get this thing tuned. Just curious of possible damage at all.

I do blow some smoke, thought it was black judging by my rear bumper. Friends says looks blueish. Did a compression test and pulled 220/225/220/220. So probably not rings. Valve seals? I know I need an adjustment. Comments?

 

When i got my first ECU from him, It ran so rich i couldnt even tune it! I got in touch with kenji and he sent me a new chip. It took care of it all. Contact him, and let him know, he should be able to take care of you.

 

I am running the Kenji/Mugen program on my B16A SiRII on a P28 ECU and it runs very lean. On the dyno with the Kenji chip with a wideband O2 sensor it runs in excess of 18:1, especially at high RPM. I am running it 18% rich on the VAFC now, and it's right at 12.5:1 at WOT where it needs to be. On a stock O2 sensor it appears very rich. Don't trust it. With the Kenji chip it lean-backfires a LOT on deceleration.

I've e-mailed Kenji about this thinking it was rich and he said it was, so I was leaning it about 11% at WOT and lord knows how dangerous that was. Once I got the car on the dyno with a true wideband O2 sensor, I found that it's very lean. Once I got the fuel right around 12.5:1, the engine put down 151HP and 109TQ at the wheels. This is with a stock 1994 B16 SiR-II with AEM short ram intake, no catalytic convertor, and a canister muffler with stock fuel pressure for a 94 Civic EX. Your results may vary, but that's my story. Hope this helped somebody.

Dougal Walker
Chicago, IL

 

Dougal,

The program that I use for B16s is different than for 1.8l engines. Sounds like you put down some pretty good numbers considering the minor mods you have done.

-kenji

 

Agreed.

 

Are you still using stock injectors?

No matter what you do with the ECU it won't help if your injectors can't keep up. About a year ago a friend and I were noodling with his Hondata and a MoTeC Lambda meter. His engine was a B17A with a short ram, ITR cams, IM and exhaust manifold (USDM). We saw very similar A/F ratios and injector duty cycles of 100% above 7500 rpm no matter what we did with the fuel maps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ITR5874 &raquo;</TD></TR><TR><TD CLASS="quote">The right rear light shines darker than the left, even the wing is covered with black particles...
</TD></TR></TABLE>

My car deposits those black dust particles on the rear too. I thought that was normal..? My A/F is about 13:1 across the whole RPM band 'til redline where it approaches 12:1. Keep in mind my car is stock too

 

https://honda-tech.com/zerothread?id=452233

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kenji &raquo;</TD></TR><TR><TD CLASS="quote">Dougal,

The program that I use for B16s is different than for 1.8l engines. Sounds like you put down some pretty good numbers considering the minor mods you have done.

-kenji</TD></TR></TABLE>

Ah ok, thanks for that info.

Yeah, I am very happy with the numbers. What a nice engine the B16 is! That is the engine that should have come in 5G Civic Si's from the factory in the USDM. Thanks for all your help Kenji!

-Dougal

 

My Kenji is super-rich... but when i ordered it, I had planned to build a 2.0 bottom end. Even with its rich fuel map, it was one of the best mods I did to my car, huge improvement over my OBD2 crap