I just got my COP system finalized and running last nite. At VERY light load around 3k or so I get some small misfires. I've tried lots of diff dwell settings based off the DSM AEM files and such....

I'm kinda figuring it may be fuel related to some small extent however it never did it before on the stock ignition. The misfires start as soon as the a/f drops over 15.5:1, which is where I have it when cruising...

Anyone have any ideas on what it may be? Or should I just richen it back up a tad and maybe that will take care of it..

 

You'll probably have to add a little load, I find my car misfires a little more often when it goes a little lean at light loads.. I did the CBR Coil thing for awhile also and didn't have many problems with a DSM ignitor and a motec box on a stock ECU.

 

its just odd to me that it does it now. I wonder if maybe the slightly hotter ignition is burning more fuel off in the light load and fuel situation and its causing a slightly leaner condition.....creating the misfire?

 

My experience was when i upgraded the ignition, I started getting better ignition and therefore a more complete burn, of course that led to the slight lean condition..

 

Thats kind of what was going through my head...just needs a tiny bit more fuel..I notice it runs a tad leaner at idle and such now as well.

Thanx for the help Jack! BTW, did you ever get your stroker/20g done? I think I saw elsewhere that you changed your mind slightly?

 

3000rpms is the cutoff point for multiple spark and likely why it is irky there.

 

3krpm mis fire with the msd dis-2 is normal.

 

The block should be going out in 2 weeks.. I decided to use an 05 turbo with the header and O2 housing, and have another setup for "fun" that I can swap on when needed which I should be recieving very shortly.. but yeah I changed my plans a little when I got word of the OpenECU reflash cable..

You might actually be interested to know that I ultimately removed the CBR959rr coils and Motec CDI-2 unit, put in Chrysler300m coils and an AEM C2DI, ultimately I put stock Evo coils, and an HKS DLI-2, the 300m coils seemed to work a bit better than the motorcycle coils, and the HKS DLI-2 and stock coils seems to work as well as the 300m coils for thepower level I'm currently at.. Go figure..

 

Thats a good point, my CDI setups are different than the MSD, and probably transition over a little differently..

But the two things I did have was the slight lean, and occasional misfire from it, and a tip-in lean what I never was able to resolve because of the stock ECU, stock Flash, and UTEC.. I have actually finally resolved that in the past few days.

 

hmm......I"ll put in the bypass plug and drive the car again and see if that gets rid of my problem. I wonder if the ignitor and coils would be enough spark for a big snail. It wouldn't terribly hurt my feelings to get rid of the dis2...it is after all a teensy bit large for my tastes.

 

If you are setup for waste fire ign with COP disable the multi-spark. They don't jive.

 

Wasn't sure you could do this... I'll have to take a look at a box.

 

LOL, that is entertaining. An MSD box with the multiple spark disabled...I just looked and unfortunately its not possible w/ this particular box.

Do you guys think the ignitor and coils (ie remove the MSD box) would be enough spark for a 50 trim and later possibly a 35 or 37?

 

It is probably an option on AEM CDI and standalone which is why he mentioned it. Vijay knows his ****, so it was worth looking into.

 

I think where you benefit most with CDI isn't so much the upper RPM, though it does boost voltage to the coils a little, the MSD portion of it has alot to do with being able to use cold plugs and large gaps, and still get decent low RPM performance.. So I don't see you having too much an issue at higher RPM with those coils and no MSD box.. just possibly poorer idle or part throttle performance without the MSD depending on the plug heat range and gap..