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cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

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megasquirt woes
Posted by: cgill
Date: March 28, 2015 01:07PM

I am at my wits end with this megasquirt stuff. I have tried almost everything and can't get it to fire.

Here is what I posted on the MS forum just now...

Here is the setup:
MS3.57x built by DIYautotune
Buick 350 ci – new engine, never started
Ford EDIS system with trigger wheel (set up with missing tooth 5 ahead of sensor)
MS Relay board
Injector wiring to relay board is as follows:
1&6 wired to INJ1
8&5 wired to INJ1 (second slot on relay board)
4&7 wired to INJ2
3&2 wired to INJ2 (second slot on relay board)

Power for injectors is from relay board
VR sensor is wired correctly
I have spark. When cranking and with a plug out the spark timing appears to be close.

I can't seem to attach the tune here unfortunately but I can email it to anyone who is willing to look at it.

I have the tune set for semi-sequential based on my injector wiring. If I have my main fuel outputs set to standard fuel it will sputter a bit. But I know this is wrong for semi-sequential so I have it set at MS3x fuel.

I tried increasing the cranking pulsewidths because that will supposedly help with starting. Not even a sputter. I pulled a plug and it wasn’t wet, even though I had the cranking pulsewidth set around 350 and then at 400 (I varied it) for the current coolant temp. There was a faint smell of fuel on the plug.
I am wondering if my injectors are actually firing based on this result?

If my injector wiring is okay and my tune doesn’t look too screwy, what should my next step be?

Thanks in advance for any help. I have been trying to figure this out for more than a week now and am getting desperate.

Chris



Edited 1 time(s). Last edit at 03/29/2015 01:45PM by cgill.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: megasquirt woes
Posted by: BlownMGB-V8
Date: March 28, 2015 01:48PM

Chris, I'd say the first step is to revert to old timey troubleshooting steps. As we all know, you need fuel, fire, and compression. So let's see first which one is out of whack. New engine, compression should be fine. But if you haven't checked it you might do that just for a baseline.

Next let's eliminate either fuel or fire. Grab a plain old squirt bottle and spray a generous squirt of fuel down the intake. Unplug the fuel pump, crank it and see if it'll fire up on the manual prime squirt. If it does, use the squirt bottle to keep it running and see if the engine sounds like you can make it enjoy running. If you can your timing is reasonably close. If you can't, look more closely at your timing advance. Before you can ever get the injector shots right the timing has to be in the ballpark. I haven't heard you say yet that you've put a timing light on it, so if you have a buddy to help you maybe he could check to see what the timing is doing while you are keeping it running. No point in me repeating where that should be.

Once you have the fire where it should run OK you can start playing with the fuel.

Now, the only real difference between full sequential and everything else including batch fire is at part throttle and idle with the timing of the shot, and as long as the fuel gets in the cylinder the engine really doesn't care when the shot is fired. Any difference in the way it runs will be very minor and usually undetectable. So you can assume fuel is fuel.

Is your line pressure right? It needs to be rock steady at full injector saturation (all injectors wide open). You can simulate this by wiring 12v and ground directly to the injectors. That is one way to check if your injectors are doing their job. You can use a "Noid Light" to see if they are getting a signal.

Divide and conquer is the old troubleshooter's mantra. It applies here as well as it ever did anywhere else. Do not automatically assume it is the controller, more often it is something else.

Jim


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 28, 2015 03:32PM

I didn't have a squirt bottle so tried some starter fluid and it started immediately but died but it did sound like it was running okay for a brief bit. I think it has something to do with my injectors not firing so I am going to focus on that.

So there isn't any issue with how I have wired my injectors together and where I have connected them on the MS relay board?

Thanks as usual Jim. I used to say "I know I'll figure this out" but after two weeks I am starting to lose confidence!



Edited 1 time(s). Last edit at 03/28/2015 06:20PM by cgill.


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 28, 2015 08:27PM

I have tested the injectors in test mode using a test light in the connector. I am not getting a pulse and not hearding anything.

Are the two wires on injector connectors dedicated specifically to power and ground or does it not matter as long as you have them all hooked up the same way?

I am grasping at straws here!


Moderator
Curtis Jacobson
Portland Oregon
(4576 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
test
Posted by: Moderator
Date: March 29, 2015 11:45AM

I grabbed your tune and log files off that other forum to see if they'd attach properly to a message here.

cgill-tunefile.msq

cgill-logfile.msl


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: megasquirt woes
Posted by: BlownMGB-V8
Date: March 29, 2015 11:46AM

Chris, you should have power applied to one side of the injectors through the main power relay and the fuses, then the controller supplies the ground. So it sounds like your controller may not be grounding the injectors, but first do a test to confirm power through the injectors. You can put a clip lead on the control side, tie them all together with jumpers, and ground the lead. That should turn on all your injectors at once, full on and allow the engine to wind up with the throttle all the way open.

BUT consider SAFETY! It would be wise to disconnect the injector leads from the controller before doing this test. It would also be wise to be able to yank the clip lead off to kill the engine.

If you do this test properly, you should be able to give the engine a pulse, crank it to fire, then pulse the injectors manually and keep it running with the throttle plate at a high idle. The more throttle you give it, the longer you will have to supply a ground to the injectors, basically letting it nearly die, grounding it which should cause the engine to rev up until it starts to choke out from too much fuel, un-grounding it at which point the engine should smooth out and increase rpms before starting to die again.

This also works at full throttle except you remove the ground before the revs get too high.

This should work as described. It is also consistent with not seeing a ground pulse from the controller, so then you look at that side.

First off, without a scope you may not be able to detect the shorter firing pulses, and with the injectors disconnected you have to supply a pull-up voltage to see anything because the controller is supplying a ground rather than power. So my first question has to be, "Is B+ supplied to the opposite side of the injectors?"

Provided all is well there, the next place to divide troubleshooting is software/hardware. Both have to be set up right for it to work.

You have a guage on your virtual dashboard that shows injector pulsewidth. What readings are you getting there? This should vary from about 1-2ms (milliseconds) to something under 25ms. 25ms is 1/40th of a second, or 1/2400th of a minute, so an injector firing for 25ms in an engine running 4800rpm is on all the time. (Two crank rotations per firing pulse) You only ever want your injectors going solid at redline and WOT so if they are going solid below redline you need larger injectors.

That gage will tell you whether your problem is in the hardware (bad wiring, fried output transistors, etc) or software (setup parameters, table entries, etc). From there you can narrow it down further.

I would suspect the injector setup entries myself, it's easy to make mistakes there.

Jim



Edited 1 time(s). Last edit at 03/29/2015 11:50AM by BlownMGB-V8.


Moderator
Curtis Jacobson
Portland Oregon
(4576 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: megasquirt woes
Posted by: Moderator
Date: March 29, 2015 12:35PM

In my browser, if I click on the msq file link (above) I see a whole lot of black text on a white background. I pulled down one of the menus in the Firefox toolbar and selected "Save File As". That let me put your msq file on my desktop.

Then I opened TunerStudio, which by default showed my my own tune file. When I selected "compare tune", TunerStudio showed me a nifty comparison of your tune selections versus my own.

I didn't find a smoking gun - someone more experienced should look at your tune and log - but I did find a couple things that might be good to change.

You'll find an injector timing table under "Fuel settings". Your table currently has "360 degrees" entered for every cell. I found that my engine idles/runs a whole lot smoother with that table filled in differently: basically "-300" up to 1000rpm, transitioning to "-220" for every engine speed over 3000rpm. Also, you've set your injector size at "252cc". I've got my injector size entered as "232cc". I expect one of us probably made a typo. (Might be me.) Under "Ignition Options", in the "Cam input (if used)" box you've selected "MAP" sensor. Did you mean to do that? (I'm using CMP there. There should be other options available.)



cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 29, 2015 01:38PM

Thank you guys!

Jim. I am concerned about doing that with my engine since it hasn't been broken in yet. I am almost convinced that you are right in that the controller isn't grounding the injectors for some reason.

When I connect the ground wire on an injector plug to a test probe and ground the probe to the chassis I can hear the other grouped injector click (I have them wired in pairs for semi-sequential). So it sounds like the ECU is not firing the injectors, but why?

Curtis, my injectors are rated at 24lbs/hr so they are a bit bigger than yours. Thanks for the information on the differences between your tune and mine. I'll change the injector timing table. As per the "cam input" I don't have a cam sensor and the only options in the dropdown are MAP sensor, MS3x Cam in, or JS10. I thought MAP sensor was the closest option. Am I wrong?

Curtis, can you post a photo of your injector timing table?


Moderator
Curtis Jacobson
Portland Oregon
(4576 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: megasquirt woes
Posted by: Moderator
Date: March 29, 2015 02:13PM

But if you did have a cam sensor, you'd connect it to the cam input pin (#32) and not to the MAP sensor pin, right? I don't know if it matters at all; it just looked a little fishy to me.

Here's that table.
Screen shot 2015-03-29 at 11.02.15 AM.png
(I don't remember who tipped me off to try these values.)



Edited 1 time(s). Last edit at 03/29/2015 02:15PM by Moderator.


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 29, 2015 02:14PM

Thanks Curtis. Why are there negatives in your table? Mine are all +360 right now.


Moderator
Curtis Jacobson
Portland Oregon
(4576 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: megasquirt woes
Posted by: Moderator
Date: March 29, 2015 02:22PM

You've got 720 degrees of injection timing to play with on a four-stroke. The convention is to think of that as -360 to +360. (You could say -300 = +420. -300 isn't equal to +60!)



Edited 1 time(s). Last edit at 03/29/2015 02:27PM by Moderator.


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: megasquirt woes
Posted by: BlownMGB-V8
Date: March 29, 2015 04:29PM

Chris, I still think you should take a look at your injector pulse times. That is the direct commanded output to the injectors. If the controller is telling them to fire it will show up there. That tells you if it is in the settings (probably) or in the hardware. You need to know which one it is before you go off trying to troubleshoot one or the other, because you just might be wasting your time on something that is working the way it is supposed to.

Jim


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 29, 2015 08:42PM

Jim. Pulse width is around 15.5 ms while cranking.


Moderator
Curtis Jacobson
Portland Oregon
(4576 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: megasquirt woes
Posted by: Moderator
Date: March 29, 2015 09:31PM

How confident are you that you have fuel pressure?


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 30, 2015 01:21AM

I have a bung welded in to my fuel rail for a schrader valve and have confirmed fuel pressure when the pump is priming and also when cranking using a fuel pressure gauge. I unscrewed the valve and fuel came pumping out when the pump was priming.



BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: megasquirt woes
Posted by: BlownMGB-V8
Date: March 30, 2015 10:00AM

Can you put an LED across the injector outputs to give a visual indication of a pulse? 15ms should certainly be more than enough to run the engine at idle, usually 2-4ms is adequate.

Ideally you would scope the outputs to confirm the pulse width there. Barring that, a setup to fire off a single injector under pressure from the fuel pump would be the next best test. That can be done with scrap pieces of hose and such. An LED from B+ to the injector output can give you a visual indication, be sure to use the appropriate current limiting resistor and get the polarity right.

Did you ever put a timing light on the engine to confirm your timing advance? I know you got it to start but from here that still seems like an unknown.

Concentrating on fuel though, let's confirm fuel can get there provided the signal is output. Your injectors clicked, fair enough, but were they under pressure? Did they spray? Do they have an acceptable spray pattern? All unknowns at this point. 24lb injectors sound small for a 350ci engine, why are you using those? Are they used injectors? Have they been tested? Unless they are brand new out of the box, that's the first place I'd look for a fuel delivery problem after checking pump pressure. It isn't hard to hook an injector up to a efi fuel pump, drop the supply line in a jug of gasoline, jumper the pump and the injector to a battery and see if it sprays. (A fuel pressure regulator in the circuit is a good idea) And no more dangerous than spraying a can of aerosol hair spray provided you make sure your hoses can't come off. (You certainly want to test that at full pump pressure before powering up the injector) If your injectors are clogged no amount of signal will help.

Now, the test I suggested earlier was intended to test this, and I understand about having an engine that hasn't been run in yet. But this is a short test and personally I'd take the chance. The initial run-in is intended to give the cam the best chance of breaking in without wiping off a lobe. So far, you should still have the break-in lube on the cam. It isn't until the engine gets up to speed and runs a bit that it gets washed away. So to confirm that the injectors are doing their part of the job, I'd risk it.

Jim


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 30, 2015 10:14AM

Thanks Jim. I have to run off to work today but will mull over your advice once I get home again.

I checked timing last night while cranking the engine. It is approximately 5 degrees advanced.

The injectors are used and you have made a good point about testing them. I was assured they worked well but you never know.

The 24lb injectors were recommended by Jim Nichols.


cgill
Chris Gill
Salmon Arm, British Columbia
(129 posts)

Registered:
08/13/2009 12:06AM

Main British Car:
1979 MGB roadster Buick 300 stroker with EFI

authors avatar
Re: megasquirt woes
Posted by: cgill
Date: March 30, 2015 11:30AM

Jim,

Would a test light work for that test for pulsing? I inserted a few strands of wire into each plug outlet, clipped the test light ground to one and touched the probe to the other wire. I then ran the injectors in test mode at 20ms. Nothing.

I am looking into getting the injectors bench tested but I think it is a software issue. I don't see where I can adjust pulsewidth in Tunerstudio but maybe I am just missing it.


MustangSix
Jack Collins

(30 posts)

Registered:
12/16/2011 10:53AM

Main British Car:


Re: megasquirt woes
Posted by: MustangSix
Date: March 30, 2015 12:03PM

Chris,

I may have missed it, but have you confirmed that you have 12V on one side of the injector lead with the power on? The other side of the injector goes to the controller which supplies the ground to activate the injector.

If you have a test LED or light, it would go across the two injector leads, not to ground.

Jack


BlownMGB-V8
Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(6468 posts)

Registered:
10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
Re: megasquirt woes
Posted by: BlownMGB-V8
Date: March 30, 2015 12:33PM

Correct on the LED, and there are several ways to do that but across the injector is probably the best as that checks the entire circuit.

An incadescent bulb is supposed to be usable but I've never been that happy with the one I bought for testing injector outputs. Filaments take time to warm up and you might miss it. An LED is instant and uses very little current so you can see that when the incadescent is struggling to emit any light at all. Typical resistor values for an LED in an automotive application are in the range of 1000-1500 ohms. You don't have to be exact. Some LED indicator lights for auto use have the resistor already built in.

Your 15ms pulse shown on your digital dashboard during cranking argues loudly against a software problem. Sounds like hardware, either before the injector connection or after it. In other words, wiring or plumbing.

Jim
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