My misfiring problem.

wes kiser · Post by **wes kiser** » Mon Sep 03, 2007 5:25 am

I ran standard B and G code for a while, and have ran extra 2 code for a while as well. I have encountered bugs with both, and in both cases the developers have fixed them very rapidly.

For them to fix it, they have to be able to reproduce the problem, or you must be able to tell them exactly what triggered it, and what moved. Many people are running MS2-E now, and it ran great for them.

Be patient and find what causes your issue. Is RPM wiggling around near the miss? What about battery voltage? If you put a timing light on it when it is missing at low rpm, what does it do? Does PW move when it misses?

baneonrt · Post by **baneonrt** » Tue Sep 04, 2007 10:50 am

Just a warning, this will be an incomplete post. This past weekend I decided to try the MS2 in my Neon. I'm having the same "miss" problem described by UnaClocker. Running Beta 8 and started tuning from scratch. It goes away when I switch to stock ignition control.

I will take some logs asap and post them. I just wanted to mark this thread so I can get back to it easily

Steve

Post by **muythaibxr** » Tue Sep 04, 2007 10:52 am

James or I will be taking a look to see what we can find (As listed in the bugs thread).

In the meantime, an msq would be good as well.

Ken

baneonrt · Post by **baneonrt** » Tue Sep 04, 2007 11:52 am

muythaibxr wrote:James or I will be taking a look to see what we can find (As listed in the bugs thread).

In the meantime, an msq would be good as well.

Ken

Yeah, I'll post when I get home. I just found this thread and wanted to mark it.

Thanks,

Steve

md95 · Post by **md95** » Tue Sep 04, 2007 8:11 pm

I will try and test this out as well on my 420a, providing i can get a few spare moments..play time has been very little lately!

Post by **jsmcortina** » Wed Sep 05, 2007 3:19 pm

Ok, I popped this on the stim and _think_ I can see some strange behaviour. However, this is simulated and I don't believe that I've updated the wheel sim to match the tooth angles in the latest MS2/Extra code.

What appears to be happening is that every so often the dwell is too short.

What happens if you raise the dwell from 1.6ms (sounds very short already?) to say 3ms ?

Obviously watch for heat in components, but the additional dwell is likely to mask any shortening and would help to back up this theory.

When I get time I'll try older code versions to see if I can see the same symptoms, plus I'll update the stim code to the right angles.

I have a few thoughts on fixing it - the present Neon code tries to use both edges of all the teeth, this might be asking for trouble as some of the gaps are quite small and might magnify crank speed variations. I can look at changing the decoder to use only falling edges of the teeth. This will take a little time though as I haven't worked on the decoder in a while.

James

UnaClocker · Post by **UnaClocker** » Wed Sep 05, 2007 3:52 pm

That does sound like something good to try, the only using one edge of the tooth.
As for the dwell, I tried increasing it on several occasions, and it didn't help. I didn't go over 2.6, because I was just over 3ms back when I was having the random missing caused by my VB's overheating to the point that they'd stop working. Maybe someone else can confirm my findings on that though.

baneonrt · Post by **baneonrt** » Wed Sep 05, 2007 3:58 pm

jsmcortina wrote:Ok, I popped this on the stim and _think_ I can see some strange behaviour. However, this is simulated and I don't believe that I've updated the wheel sim to match the tooth angles in the latest MS2/Extra code.

What appears to be happening is that every so often the dwell is too short.

What happens if you raise the dwell from 1.6ms (sounds very short already?) to say 3ms ?

I am experiencing this problem at 5.0ms of dwell using non current limited IGBTs. This duplicates the factory ECU dwell and charge current.
It also runs great on MS1 Extra with this setup.

Steve