Can someone test my MegaSquirt II 3.57?

[jangell]

I've run out of ideas about why my 3.0L MegaSquirt conversion won't run. Would someone here be able to test my ECU? The unit is a MegaSquirt II 3.57. I figured I'd mail it out to someone who has a working conversion, and they could flash it with their tune and see if it works in their car, then mail it back to me. I'd pay shipping both ways, of course. Although if anyone is in the souther Massachusetts area, I'd be happy to meet them for a test.

I just can't figure out what is wrong. I've documented what I've tried in this thread (tunes attached to posts in the thread). It was actually idling properly. I then re-routed the harness a bit (which required lengthening a couple of wires), replaced a coolant hose and fixed two swapped coils, and now it won't start. It cranks, occasionally fires a cylinder, occasionally backfires, but won't actually start.

Of note:
- Fuel pressure is good (there's a gauge reading ~40 PSI in the engine bay). Fuel is fresh (a few weeks old).
- All plugs and coils are firing (I pulled each plug/coil pair and tested them separately while cranking).
- All fuel injectors are good (pulled them and put them in bottles, ran MS in test mode to check spray, replaced the one bad one I found).
- All coils are connected to the correct plug banks.
- VR sensor is correctly positioned 6 teeth before the missing tooth, and ~1 mm from the gear.
- Oil pressure is good.
- MAP reading is good.
- RPM reading from EDIS to MegaSquirt via TunerStudio looks good.
- TPS and temp sensors read correctly.
- Ignition timing to EDIS appears to be correct, other than the fact that the car doesn't seem to want to start.
- Removing the EDIS SAW signal from MegaSquirt has no effect.
- Changed batteries for good measure.

Most recently, I replaced the near 40 year old bulkhead connectors with a single modern 31 pin weatherpack bulkhead connector. I traced and tested every wire as I went, making sure they were good from the MegaSquirt DB37 connector, EDIS connector, fuses and other original connections in the car to their ends in the engine bay, and both crimped and soldered each wire before inserting its pin into the connector. Everything looks good and tests positive.

The most important note here is that the car was idling before. I just don't know what has changed to break it. Since I've tested everything else, I'm wondering if something has gone wrong with the MegaSquirt unit itself.

Thanks!

-- Joe

[dn010]

Did you try the jimstim or other simulator boards with your ECU since?

[jangell]

I do have a Stimulator. I got it so I could do tests with a computer-based instrument cluster without having to work inside a running car all the time. I played with it a bit a few weeks ago when I completely failed to get CAN Bus to work. In fact, I seem to get no useful signal from MS at all for CAN Bus, even with the right settings in TunerStudio, although my oscilloscope is older than the DeLorean and is a bit hard to read (really need to get a new one that doesn't weigh as much as a car battery...)

...of course, I brought MS home, but I left the serial to USB cable at the garage, so I can't actually look at anything in TunerStudio. I'll have to run down tomorrow morning and grab it. All I can do right now is watch the fuel pump light turn on and fuel injector lights flash as I change the RPM dial.

-- Joe

[opethmike]

I no longer have an EFI PRV in my car, but I do still have my 3.57 MSII ECU. I could lend you that if you'd like.

[jangell]

That wold be great! I really wanted to try that, but I didn’t want to deprive anyone of a working car while they mailed me their ECU. I’ll PM you my address, and if you want to PM me a PayPal address I can send you the shipping payment.

Thanks!

— Joe

[dn010]

Any updates?