Can you verify it's not my MSQ?
 

Hi All,
Breaking the first rule of Fight Club I decided to change a few things at once. I rebuilt the 'hack job' that was my MS3 and MS3X wiring harnesses, I installed a set of LS2 coils on a SadFab bracket with new custom Magnecor 8.5 wires with new NGK plugs, and I changed the wiring for my injectors from batch to sequential.

The wiring is now as follows:
Cylinder 1 - Injector A / Spark A
Cylinder 2 - Injector B / Spark B
Cylinder 3 - Injector C / Spark C
Cylinder 4 - Injector D / Spark D

I'm hoping i just have an incorrect setting and it is something i missed but would appreciate anyone that is familiar with the settings for LS2 coils and sequential fuel and spark to take a look and give me any advice. I've spent quite a bit of time looking through past posts and feel somewhat confident in it but it no worky... I'm hoping there is just some simple setting or mis-wiring i'm doing that is easily fixed.

I will say that it did start on these setting initially and was a semi-rough idle at about 5-600 rpms a couple blips of the throttle yielded a rough accel on the engine and then a slow return to idle. After about 20-30 seconds of idle it died out and not will not restart.

Thanks again for your time,
-Jeremy

iirc, the default firing order is
1,3,4,2
A,B,C,D

If you wired it differently, I believe there's a setting in tuner studio where you can change the firing order to how you wired it. I don't have a MS or tunerstudio installed so this is just my guess.

There's also the output test mode to check if your coils will fire as well. May wanna check to see if you have spark on all 4 coils.

Thanks for the reply! I saw this in another post and I'm not sure I understand the theory behind it. Does it mean the spark order is 1,3,4,2 and the injectors fire in the order A,B,C,D (1,2,3,4).

Sorry, I'm slightly confused on the Numbers and Letters...
-J

I'm no expert but I think you want the injectors firing in the same order your coils fire off for combustion purposes.

That was my assumption as well but I have seen the 1342 ABCD in another thread. I'm just not sure of the meaning...

MS will always fire the coils and injectors in order of A-B-C-D, but you want them both to fire in 1-3-4-2. So wire Injector A and Spark A to 1, Inj B and Spk B to 3, C to 4, and D to 2.

Thanks Ace! After re-configuring the wiring i've got a fairly consistent start now with a little throttle massaging. Once it catches it is still a fairly fragile/rough idle around 500 rpm's. When switching from batch fire injection to sequential injection do i need to rework my fuel tables? The AFR's are running almost full rich on my WB O2 sensor. As a side note i pulled each of the plug wires from the coil's and the receiver end of the D585's all sparked against the mount so i'm fairly confident I have good spark. (Other than adjusting the dwell settings for the D585's i didnt change anything else related to the ignition in the MSQ.

Thoughts on the fuel table or what else i may be missing after converting to sequential injection.

Thanks again for holding my hand through this process and any thoughts are much appreciated,
-Jeremy

Well, I feel like i'm getting closer...
After some further digging I got the IAC wiring sorted and now i have a reliable start and idle around 1200 RPM's, It can breathe. The idle and accel now feels very rough... Attached is my current MSQ's and DataLog for the minute or so I pulled plug wires to verify i was getting spark at all 4 cylinders. I'm beginning to wonder if this is a timing issue. Other than converting to coils nothing physically changed on the engine to affect the timing. Is there a setting in MS that would affect timing by converting to sequential firing from batch firing?

Thanks again for any light you can shed on my darkness...
-Jeremy

MOD's can you please move this thread to the MegaSquirt subforum and delete this post. My apologies for not posting in the correct subforum in the first place.

-J