Single coil 4/2 CAS test w/MSD6a Nissan 240sx

KaPower · Post by **KaPower** » Wed Oct 10, 2007 9:58 pm

I'am using a 4/2 CAS, w/ beta12. MSD6a, with single coil and my stock Nissan distributor. I have not tried this configuration on any other beta codes.

Engine starts up much faster then with the OE Nissan optical CAS, and has not kicked back once (yet).

Engine starts up runs good for 10-20 seconds then hits a wall and stumbles into a rut at 500-700rpms, and the engine starts to run very erratic. I can not accel out of this rut. I have to shut the engine off, and restart to make it run good. It is very repeatable, as it does this every time.

The datalog shows me holding the rpms at 1500rpm and 3000rpms I do not lift off the throttle when the rpms fall.

Post by **muythaibxr** » Thu Oct 11, 2007 7:08 am

We'll take a look.

Ken

KaPower · Post by **KaPower** » Thu Oct 11, 2007 8:40 pm

I reflashed my ECU today, no change. So it was not a corrupt re-flash.

- All of my fuel injectors are opening when the misfire occurs.
- I can see dropped ignition events with my timing light.
- Never once have I lost sync
- Tach input circuit's consist of the neon mod'd hall circuit, with a 5v/1k ohm pull up to js10 for the second trigger.

I was able to get the engine to misfire and come out of the rut and run decent, I can see a diference with the timing light, between normal running and the misfire rut.

I'am going to wire up my Toyota wasted spark coil/ignitor packs and see how it runs on wasted spark. I beleive that all the other 4/2 CAS testers used a wasted spark configuration, since the stock 4g63 ignition is a wasted spark system.

md95 · Post by **md95** » Fri Oct 12, 2007 6:54 am

Yeah i dont think anyone has even tried running a single coil with 4/2 CAS. The option is there to run single coil, but using an ignitor and a wasted spark coilpack is superior to a distributor anyway, and it's easy enough to hook up and run. My 4/2 CAS on the 4g63 runs excellent(just a slight glitch, but still on old alpha code)..Will be upgrading before too long.

KaPower · Post by **KaPower** » Thu Oct 18, 2007 9:28 pm

Any chance to get my config scope'd? My timing light is showing missed spark events.

I've never used D14 as spark A, to control my MSD 6a before now. So I'am not sure if I have a fualty transistor or something. Maybe my 4/2 CAS has an issue? The thing is I never loose sync. If I had a intermittent fualt with my CAS signal would I loose sync? My problem is intermittent. At times my engine runs very well, and when it runs bad no matter how hard I try I usually cant get it to rev above 700 rpm.

I now have my board modified to control a set of Toyota wasted spark ignition coils w/built in ignitors. I should have my engine running again this weekend. (Fingers crossed)

Jason M

KaPower · Post by **KaPower** » Sun Oct 21, 2007 3:58 pm

Wasted spark is not working for me yet. I'am using 330ohm resistors and a 5v pullup to trigger IGT on my coil packs, with the (-) legs of D14 and D16. spark output is normal going low. normal dwell control, 8ms cranking, 3ms running. I have spark but it looks weak at times. Blu-ish in color.

Looking at the Toyota FSM the trigger for the ignitor on a scope pattern, it stays low, goes high and then releases (goes low again) so the high period (5v) must be dwell control period and the going low part is the spark trigger.

Who knows how long it will take to get the 240 running, it Could be awhile!

KaPower · Post by **KaPower** » Sun Oct 21, 2007 7:11 pm

The 240sx is running again! It starts so much better! My old CAS with 1 crankshaft position signal per 180 degs was not enough to get the brute of an engine started very well...

Ignition timing *appears* to be solid. Never lost sync once. Idle is a little shakey, but thats not abnormal due to my very small required fuel number 2.7ms! Dwell & VE also needs to be fine tuned. I have not run on MS for several months. Lots of changes!

More testing to come. Back to the original subject...

There must be a problem with 4/2 CAS single coil mode. Or maybe the fixed dwell option. I was using fixed dwell mode for my MSD 6A ignition Box.

With standard MSII when using an MSD 6A box I had to change the ini file for IIRC, max dwell duration. It had to be changed to 25.5ms. currently it's 8.0ms. Maybe I should of tried that. just an idea...

KaPower · Post by **KaPower** » Tue Oct 23, 2007 9:11 pm

I'am in the proccess of permanently installing my 4/2 CAS, wasted spark coil packs & wiring. I'll keep my MSD single coil setup installed in my car for awhile. I can modify my board and reinstall cap rotor wiring ect... to test out 4/2 cas single coil mode if needed. If you all don't need/want me to test then please let me know.

Jason M

KaPower · Post by **KaPower** » Sun Oct 28, 2007 6:08 pm

So whats up? Do you not think theres a problem, not enough time to "look into this"? I don't plan on running the single coil setup, but it is poosible that others may. If the option is there it should atleast be tested and known to work if it is going to be released in V2.0.

Post by **muythaibxr** » Mon Oct 29, 2007 7:21 am

I think we stopped looking since you said you got it running.

One of us will take a look before 2.0 is released.

Ken

KaPower · Post by **KaPower** » Mon Oct 29, 2007 10:49 am

I got it running using wasted spark, single coil mode does not work properly.

KaPower · Post by **KaPower** » Sun Nov 18, 2007 7:46 pm

I'am running out of time to test single coil mode... Should I just bag the whole Idea of testing out a fix?

KaPower · Post by **KaPower** » Fri Dec 14, 2007 6:04 pm

Your welcome for testing out this code, I must be too much of an idiot to accurately test for beta, since I have no experience with code writing... I must be imagening the single coil issue.

Post by **muythaibxr** » Sat Dec 15, 2007 9:11 am

Not sure what the attitude is for. We never said we wouldn't look at it. James and I are just swamped at the moment. I intend to try to look at some of the reported bugs this weekend and see if I can fix them...

Ken

Post by **jsmcortina** » Sun Dec 16, 2007 1:44 pm

I cannot replicate this fault on the bench. The "dwell" period is short below about 400rpm, but that doesn't appear to be what you are reporting.

James