Megasquirt Support Forum (MSEXTRA)

MS3X pre-assembled. 3.57. TS v 3.0.22, running the latest 1.5.0
My truck will not start. In test mode, the spark is good, injectors clicking. When cranking, I have no spark or fuel. This on LSJ Ecotec engine. GM 4x cam, 60-2 crank set at 120* btdc angle. During cranking, tuner studio shows cam and crank synced. Currently set at full sequential, poll level.
I am new to MS and tuner studio, but a quick study.
Laptop is next to me if you would like to hear any of the settings.

If it works normally in test mode, why is it not working while cranking?
Any help greatly appreciated.

here's the msq. not sure what good a few seconds of cranking will do for logging. I'll log it if you need it.

MSQ attached

switched to wasted COP and semi-sequential, still nothing. here's the msq and datalog of start attempt.
I could really use a hand here. It took two years to finish this truck, and it all comes down to squat if it doesn't F'n run.

Thanks.

That CSV file is empty. Regardless, we need regular run log (MSL); and maybe a "tooth log" would help, too. Yes, even a few seconds of logging can be useful.

I gotta ask... have you checked ignition timing with a light, while cranking? If you have no spark (while cranking), you can't have any confidence about that "tooth #1 angle" yet.

well, I had removed the crank position sensor, and counted the teeth back to the sync (missing teeth) and counted 20 teeth. So it should be 120*.

I'll get another log. Still trying to figure out how this program works.

I have not put a timing light on it. I don't have one.

You need a timing light.

attached MSL log with tooth logger running. Well, if i did it right that is.

file too big. Tried a shorter log.

that's odd. I just checked the log and its showing no rpm, but the gauge on dash mode shows 300ish rpm.

Was the engine cranking during that MSL? The "battery voltage" never dropped, that always happens when the engine is cranking. What kind of CKP sensor (VR or Hall), and how do you have the pots for it set? Counting the tooth offset physically can (and often, for me) get confusing. Rely only on the timing light to set the tooth #1 offset. You are going to want a light anyway, to confirm timing is OK all the way through the rpm range and other troubleshooting procedures.

yes, it was cranking. I had a battery charger on it.

VR crank sensor (two wire) on 60-2
I don't know what you mean by "pots"

ok, I'll pick up a timing light this weekend.

here's another MSL file. I hope this helps. Shows RPM anyway

The code is not set up correctly to match the signal that the crank/crank sensor is sending.

so you see something wrong? excellent. Steer me in the right direction please.

What I am seeing is a repeating lost sync error. I do not know the specifics of your motor.

I know some of the specifics of the engine. This is a 2007 Chevy Cobalt SS LSJ (supercharged 2.0L) engine.

right now I have it on semi-sequential, so cam signal (gm 4x) should not be in use right now. I could switch back to full sequential. Unless you mean something else is out of sync.

"The code is not set up correctly to match the signal that the crank/crank sensor is sending."

I'm confused by that. The OP says it is a 60-2 wheel (58X?), and that is what is set in TS; with wasted COP. That is certainly in the FW code.

OP, was the battery charger still there for the most recent log? Just curious, because that recent one clearly shows cranking and a whole lot of sync loss. There is no surprise about the sync loss if you have no clue what the "pots" are. On the mainboard are two potentiometers, R52 and R56, that have a little screw to adjust them. For a VR CKP sensor those pot screws should be turned CCW until you feel o hear a "clicking" from inside them. Seven turns should be enough, but I tend to go 15-20, more turns won't hurt anything as that "click" is a little clutch that releases when the pot hits the end of its range. Obviously, the manual explain all this better.

the last log did not have the charger hooked up. Should see voltage drop.

I had no idea about the potentiometers on the main board. I'll pull the box and turn them CCW.

new MSL file. no battery charger. Pots turned CCW

Post a tooth log, now that the pots are set full CCW. Both the MAT and TPS are looking strange, and both are on the 5V ref, so real soon we will need to dig into that. But right now I want to see if you now have a decent CKP signal.