Long story short, was running v.2.2 board, second VR. Had the car running, put it all together and now no spark. I built a V3 board that I had purchased for another car, got that in, It has RPM signal, all the LEDs are lit and seem to be going to their correct coil. Still no spark. so I have a V3 board MS1 spark negative. Coil specs out, and has 12V, i even tried another coil just in case, nada.

any help or advice welcome.

 

Are you sure you connected the pullup resistor to the correct side of the LED?

 

pretty sure, They are attached to the side closest to the DB connector, the negative lead. Is that correct?

 

i checked continuity between the negative lead of the LED and the negative side of the coil with no issues. I suspect I have something either miss-wired (i have checked A dozen times however) or perhaps miss soldered. My big hang-up is the fact that I had it running with my V 2.2 board using errors daughter card, then no spark with it. I got frustrated with all of the extra boards floating around and decided to build the V.3 board. Same problem. This makes me believe it is something post megasquirt but i can not figure out what. Items I plan to check:

-Proper pull up resistor:
(4.7K not 47K, damn bands on these all ways f me up)
-12V continuous to coil:
(I have checked and it does get 12V, but i do not know what happen once the ignition is turned)

Items I have checked:
-12v to coil
-Ground continuity between negative side of leading coil and D14
-coil resistance (between - and + terminals)
-RPM signal checks out
-Injectors work
-no spark on any coil (trailing nor leading)


Anything i am missing

 

here is how i have the thing wired

 

Side closest to the DB9 sounds right to me.

That's an odd way of wiring it. You ignored all those wonderful spare outputs.

But as long as pin 7 isn't tied to ground it should be fine.

Wait a sec...ground from negative of coil to D14? That doesn't sound right. The 3 LEDs should go to the appropriate wires on the ignitors. The coils are driven by the ignitors and not the 'Squirt directly.

 

sorry thats what i mean, To the wire connection at the ignitor. Yeah those spares are nice, i had actually intended for them to become boost control etc...we will see if i can get the damn thing running first.

 

here is my .msq if someone could ensure i am not missing something i would appreciate it

 

I'll take a look at home tonight or tomorrow. If someone beats me to it, that's fine too.

Ken

 

Looks good to me besides the cranking PW...WAY too much. Just set it to standard prime and 10 as as starting point

Other then that it's fine assuming the CAS is stabbed in the standard position.

 

thanks! I will adjust down the PW. Well I checked the pull-up resistors and even decided to replace them with a non-radioshack version (to no avail). I just can not figure it out, I even tried another CPU just in case with no luck. REALLY FRUSTRATING! Is there anything I could have missed with regards to the boards construction? I did not bridge anything in the ignition circuit, however I thought that was only done if you where driving a coil directly. I posted an image of the board, I will try to post something with a little more detail.

 

how do i diagnose if the line is grounding out for a spark or not? I would like to eliminate the computer as the culprit, however I have no idea how, do i need an oscilloscope to determine if it is actually reacting when it is supposed to? Should I totally reset the CPU and start over? could my .MSQ somehow be corrupt and cause this?

 

Do you get RPM when you crank? Does the RPM constantly update while cranking or go to around 200 or so and then just stay there?

Ken

 

it seems to constantly update, I have attached a datalog of my last attempt to get spark out of it. I checked the ground at the coil to the body which is fine, and i added another just to check with no luck. when i check the resistance at the negative side of the coil it is constantly infinity, which obviously means it aint sparking, I am just running out of ideas. In the datalog there is a moment after i stop turning the engine over where it sits at an RPM for a bit, could that be the same problem as your describing ken? What is the problem, cause i will check it out anyway!

 

Here are a bunch of pics of the computer finished

 

I fiddled with the hysteresis, and the zero-crossing pot in an attempt to get rid of that hesitation to reset to zero of the RPM with no luck (plus still no spark). One curious thing i noticed is while attempting to get the RPMs to go to 0 with the hysteresis adjustment, it never did. I don't know if that matters or not, but i am at my wits end here.

 

Would the Jim stim help me out here? seriously, wits end.

 

Are the LEDs flashing or dimming when you crank?

Ken

 

no flashing, perhaps a little dimming, but it seems like a consistent dimming of the entire electrical system from the starter load? maybe?

 

well I have no idea what I did, but it now has spark! God I hate that. thanks for the help, I figure out what I did I will report back

 

you should let me know what you did, i was driving my car just fine then the rpms dropped off my car died and then wouldnt start and i have no spark now!!!! could a bad alternator cause this?