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Megasquirt not running

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Hey guys, recently finished wiring up my megasquirt. It doesn't run. I am struggling to find the source of the error. For some reason I am not permitted to load up my log files or config files.....if someone could tell me how that would be awesome.

 

My setup is as follows:

 

I have the direct coil control mod installed directly from DIYautotune.

The coil has power, and the negative side is connected to MS.

Two sets of injectors, 3 and 3. They are each wired to a bank on the harness. 

IAT on the J pipe, welded bung.

MAP sensor hose is not cracked or kinked, attached at manifold. 

I have tested power at all locations, I have spark.

AEM wideband with analog output wired to MS, calibrated appropriately and reading correctly.

Temp sensor is wired correctly and reading correctly.

Distributor is wired with a step up resistor, and wired according to the posted configuration. (Power, ground, signal with setup)

 

If there is any other information I can provide, please let me know. I have a 1976 280z, running stock block, head, and everything except for a 83 dizzy, j pipe, turbo setup, etc. 

 

Thanks in advance!

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The engine is cranking with spark, and not running. I realized it is pulling a 10:1 AFR while cranking, so right now im working on bringing that down a bit. My plugs might have been fouled from trying too much while that rich.

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Cranking

 

If it's not running, you are not burning any fuel, making any AFR measurement completely useless.  AFR is only relevant when the engine is running.  Since you are getting fuel out of the injectors, I would speculate your ignition timing is off by a whole lot.

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You've been lulled in to the false sense that the computer or phone screen will tell you all that you need to know about the outside (inside in this case) world.  Happens to all of us.  I've found myself checking weather pages to see what's happening outside instead of just opening the door.

 

Remove a spark plug and look at it to see if you're flooded.  Use a timing light to see when spark happens.  Check fuel pressure with a gauge.  Real touchy-feely stuff, right at the actual engine.

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Well my timing is direct on with what MS says, as verified with the timing gun. Phil at DIYautotune suggested that my injectors might have been fried and stuck open, hence the 10:1 AFR when cranking even with injectors completely unplugged.

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Well my timing is direct on with what MS says, as verified with the timing gun. Phil at DIYautotune suggested that my injectors might have been fried and stuck open, hence the 10:1 AFR when cranking even with injectors completely unplugged.

Do you have a fuel pressure gauge?  If an injector is stuck open, your fuel pressure will drop to 0 immediately when the fuel pump stops.  If you don't have a gauge then I would let the fuel pump cycle a bit by turning the ignition on and off a couple times and then wait a minute and loosen a fuel line.  If a little fuel sprays out, then you don't have a stuck injector.

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Alright, I don't have a stuck injector. I tested them each with a 9v battery, they all fire fine. I do have fuel pressure, I have a gauge. It is holding pressure, so there is definitely not a stuck injector. I'm beginning to think my problem lies in my PWM. Is 2% duty cycle reasonable for cranking? It seems low for me. I am considering going back to dropping resistors honestly......

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I thought the injectors were set to a specific ON time while cranking, not %, 2mS (2 milliseconds) would not be unusual.

 

What are the parameters you set for PWM?  On time, %, and frequency IIRC.

Edited by SleeperZ

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I did examine plugs. They were wet, after a day of cranking and not starting. I bought drop resistors to eliminate all PWM values. I followed a writeup on hybridz, and they stated eat injector should get a 6 ohm 25 watt resistor. I could only get 5 and 8 ohm resistors, in 25 watt. Which would I be better off with?

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I think you are on the right track to back up and try something you know has worked in the past.  When I have problems starting an engine with megasquirt I go back and follow the first start guide.  Like others have said, verify timing with a light.  And then work through all of the basics for first start:  is MS set to correct firing order, priming pulse settings, cranking pw settings, cold multipliers, etc.   You said plugs are wet, but we don't know the context.  Did you dry them out and then crank for two seconds and see them wet.  Or, did you turn MS on and off several times plus some cranking and then see them wet.  Keep at it, we will try to help.  

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Just verify each setting regarding timing events and make use of the test panel. 

 

Are you getting RPM readings during cranking?

 

Haven't mentioned which megasquirt you are running. I think MS2 can run both styles of injectors so you don't even need resistors if you have the right settings. 

 

Feel free to hit me up if you need someone to take a look. I've been playing with mine a fair bit recently.

 

Edit: Also do you have the DIY wheel for the dizzy? I always get confused, but I imagine you are running the optical dizzy and if I remember the optical dizzy needs a different wheel from DIY to communicate nicely with megasquirt.

Edited by seattlejester

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Jester, IDK if you are busy today......but I noticed you are in the Seattle area and I could definitely use someone who has experience with the setup to look at this first hand.....I would SERIOUSLY appreciate it. Also, I am running the DIY wheel, and I believe I have the settings configured correctly for it.

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Seattlejester stopped over yesterday, we got it running around 12:30 AM. My oil pump shaft is 180 degrees off, so after swapping the plugs 180 degrees on the dizzy it started right up. Thanks to everyone for all the input and help, I can't believe I missed that......hindsight truly is 20/20.

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