MicroSquirt.com read only forum (Jan.15,2018)

Sorry to gatecrash this post. I am having an identical problem.

Have installed my Microsquirt in place of a fully functioning Megasquirt 1.
Engine was running fine. Was able to transfer tuning tables over to Microsquirt.

The injectors respond to the "priming pulse" but will not respond to the tach input
to start the engine. I have taken the tach input from the same source - tach signal
from my Dyna2000 ignition system. I have tried all of the other possibilities with other
inputs. Optoin+/Optoin- - neg. side of coil. even tried VRIN2+ and have been through
TunerStudio many times.

Will be following responces and suggestions with interest.

Have a look at this post for what seems to be a very effective coil -ve trigger circuit.

http://www.microsquirt.com/viewtopic.ph ... 86#p151772

The link has evapourated; here's the circuit:

Thanks for the responce.Built the wire connector as per diagram - great - engine started 1st rotation.
Problem solved. Thanks again.

dontz125 wrote:Have a look at this post for what seems to be a very effective coil -ve trigger circuit...

Now that should go in the manual, as this would make lot of sense for EFI conversions to carbed motorcycles

24c wrote:

dontz125 wrote:Have a look at this post for what seems to be a very effective coil -ve trigger circuit...

Now that should go in the manual, as this would make lot of sense for EFI conversions to carbed motorcycles

I'm happy to see another satisfied customer for that circuit. It's Matt_GSXR creation. His stuff is always good.

The project of installing my Microsquirt in place of the Megasquirt 1 has hit a major speedbump. By installing the - Matt_GSXR - tach driver I was able to successfully start and run the engine on fuel only using a DYNA 2000 ignition system.

Next step was to install the Microsquirt ignition drivers. Followed the 'Microsquirt Dual Spark' instructions for 'Indepenent Dual Ignition' (4 cylinder wasted spark). Dyna 2000 has 2 reluctors 180o apart with a single button magnet rotating on the crankshaft nose. I assume this is a Hall Effect system. Filled-in as much of the information I could under 'Ignition' in TunerStudio and tried to start the engine. No success. The injectors will not respond to any configerations I try. Have read and re-read the manuals,and gone through every posting concerning tuning ignition on the forum. I have replaced the Dyna2000 reluctor plate with the much simpler DynaS reluctor plate without success. Microsquirt and TunerStudio do not want to play with the Dyna System.

To try and get my racecar back on the track I have gone back to the -Matt_GSXR driver for fuel only. I am getting a healthy strong spark from the coils -but - the Microsquirt will not fire the injectors.I get a priming pulse, so I know the injectors are working. I can 'pulse' the priming injection to provide enough fuel to briefly fire the engine.

As a high level of frustration has set in - I can only think that I have set something in TunerStudio that will not allow Microsquirt to fire the injectors.

Any advice/opinions/help would be appreciated.

Reynard923

If the sensors are reluctors, then you need to use the VR (Variable Reluctor) inputs. The injectors won't work because you're no longer using Matt's circuit. You can't run coil -ve when the uS is driving the coils!

Do some reading on the Dual Spark trigger system; if I was at my desk instead of on my phone. I'd post a link.

Post your. msq file, and let's have a look.

Reynard,

The most common causes of this are:

- the TPS is not hooked up. If the wire is left 'floating' the ADC is driven slowly up, and soon reaches the 'flood clear' value where no fuel is injected. If you are not using a TPS, you should ground the TPS wire through a 1K Ohm resistor. If you have a TPS, make sure it is working and reliably shows the throttle position in TunerSudio.

- the injector opening time is set too short, and at low pulse widths the injectors never open. If your injector opening time is less than 1.0 millisecond, you might try changing it to this value.

Lance.

Sorry for the delay in responding - had to rebuild a burnt out starter.

dontz125 - went back to 'MicroSquirt Dual Spark' with a more detailed look. Missed the fact that I
had to 'earth' the coax shield (pin33 - VRIN-) when connecting Silver centre wire (pin32 - VRIN+) to
reluctor #1. Pin4 - VRIN2+ to reluctor #2. Coax shield was very tricky to connect to a Weatherpak
connector.

In TunerStudio I can see a responce to the tach input on the rev counter, dwell value and ignition advance
but not a value for injector pulse width.

Still unable to get the injectors to fire during cranking mode.

Lance - checked the TPS values - 30 to 532. Advancing to 100% when opening the throttle.
Injector opening time is set at 1.0 millisecond.

Still can't get this engine to fire !! I have considered opening a new project in TunerStudio and downloading
the functioning program from my MegaSquirt 1.
Would you consider this a good move ?

Reynard923

Hi dontz125,
attached is my msq.file for the current tune
and a log for the attempt at starting, plus a log
of a successful engine run in Jan. this year.
Hope you are able to see something I have missed.