420A New Megasquirt install and no spark or fuel

[VelocitàPaola]

Made it run. Sort of. What did you do for alternator control.

https://www.ebay.com/itm/Standard-VR125T-Voltage-Regulator/274395314241

Your local parts stores should have them in stock too.

 

[biglady112]

https://www.ebay.com/itm/Standard-VR125T-Voltage-Regulator/274395314241

Your local parts stores should have them in stock too.

I actually just got back from the store with that exact one.

Any advice on speedometer control running this as a full standalone? I was able to get the tach but, obviously no speed without the factory ecu.

 

[VelocitàPaola]

The vehicle speed signal is a direct connection from the VSS to the speedometer. You might have to give the sensor power (+8V, IIRC) and ground if you removed the factory ECU altogether, but it should work otherwise.

 

[dsmcrzy]

^thats correct. That’s how I had mine when I still had the stock gauge cluster installed. For the tach you can use of the of MS outputs and feed that into the stock cluster. I’ll check my old notes in the morning and post how I did it.

 

[biglady112]

I already have the tachometer working . That was easy. I will dive into the speed sensor tomorrow.

 

[dsmcrzy]

The speed sensor signal is a yellow wire with a white stripe. The signal splits and goes to the stock ECU and up to the gauge cluster. As long as you are still feeding it with power and ground it should work... also depending on how much of the stock harness you have removed.

also found this in my stash of printouts for the alternator control if you don’t have it.

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[biglady112]

I already have the voltage regulator in and working. It is bolted and grounded to the passenger side intake manifold bracket. The alternator is charging.

the stock harness is still in the car. I just need to feed the sensor power and ground.

 

[biglady112]

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All done. Ran out of clutch quick, which I expected. She is taking the car home this afternoon though. She has never even driven it before.

 

[dsmcrzy]

Glad ya got it going. What’s with the paint? Or is it dirty?

 

[biglady112]

It is actually a vinyl wrap. That is what she chose. Too bad about the clutch which I warned her about. It started to slip after back to back runs at 10psi. It would hold one gear at 11psi. Multiple gears and no go. When she is ready it will come back and I will probably do the clut chi and take it to the Dyno and turn it up. I am sending her home at 7psi.

it actually was kind of quick and was spinning the tires at 10psi.

the megasquirt wasn’t that bad. I actually really like it. The targets were not that far off. It didn’t take long to tune it at all.

I had to play with the VR conditioners some as it would not rev past 5,800. Figured that out and now it zings right to 7,200 without issue

 

[dsmcrzy]

Yeah it’s a nice system once you get the hang of it. I got mine as a kit and assembled the whole thing so I set all that up as I went. I have had mine in the car for like 9 years now. Really no hardware/software issues.

 

[motomattx]

I have been installing one of these exact units ms3x into a 420a car also with no factory ECU, been having the same problems. PLUS after the first time trying to start it we lost all communications with the ECU, took it home and found the daughter board had a fried processor.

I go to the forums and ask how to get this thing fixed or is I can get a discount on a new daughter board and I get crickets for a week, then a response telling me to contact a certain member and he then tells me he can repair the daughter board for $120 and doesn't know why they go bad like that, he wished he knew. I figure that $120 is better than $230 for a new one, I ask where to send the money and the part, and again crickets for a month. We end up buying a new board and install it, back to turning on again but there's zero support for it and we don't realize that the main board is only capable of putting out spark to one coil. We didn't want to have to use the expansion board right away, we just wanted to get it to start first and go from there but apparently that wont work. No spark while cranking but spark on one side of the coil when in coil test mode, the tach on the screen moves when we crank the car so I know its getting a crank signal.

My question is: do we HAVE to use the ignition outputs on the expansion board with the MS3x to get spark during cranking or should we be getting it on the main board while cranking on at least the one coil output?

 

[dsmcrzy]

You should be getting spark during cranking using the 1 main board spark output. I am assuming this is a preassembled kit like biglady had. What solved his issue with spark was adjusting the pots on the main board to get the crank signal to come in appropriately. I would look at the tooth logger and see what that is showing.

Here is the thread over on msextra.
https://www.msextra.com/forums/viewtopic.php?f=131&t=73964

 

[biglady112]

I had no choice. I had to go with the ms3x and the quadspark. There literally was no other way it was going to work for me otherwise.

my he good news is her car is doing great. It will be back in a few weeks with a good clutch and I will be taking it to the Dyno to turn it up as far as I can as safely as I can.