Staged injection blues

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Subwat
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Staged injection blues

Post by Subwat »

The car: 65 Fiat 1100 station wagon, rear suspension/transaxle: 72 VW Type 3, Engine: 84 Subaru EA-81 MPFI Turbo 1.8 liter. This has been running very well for about 2 years with MS3X full sequential and Ford EDIS ignition. The only problem has been poor fuel mileage, which I believe is due to poor atomization and poor air/fuel mixing (early 80's injectors and combustion chambers). The Firmware is: MS3 1.4.0

I decided to experiment with a single injector (Bosch EV 14) placed further upstream in the intake manifold. This resulted in a very poor idle and poor shifting (if I released the clutch normally after a gear change, the engine would slow the car, unless I revved it a bit and slipped the clutch as if starting from a stop.) However, once the engine was up to 2000 rpm it ran great, and might have been running stronger than with MPFI (seat of pants test). The intake air temp was reduced and hills that my knock sensor showed knock (and pulled timing) showed no knock.

I had a road trip scheduled (Los Angeles CA to Tampa FL) and no time to refine things. I decided to run the single injector, since it would be freeway with only rest and fuel stops. The engine ran great and my fuel mileage increased 5 mpg over MPFI. This was using the same fuel table as for MPFI, and I'm sure I can lean that out a significant amount.

In some spare time in FL, I'm trying to set up staged injection but I've run into a weird problem, I can't get the engine to idle. It acts as if it's trying to idle on the single injector, but it's supposed to idle on the MPFI injectors. I'm trying to get it to run on the stock MPFI injectors at idle and low speed, then shift to the single upstream injector and drop the MPFI injectors out totally at higher RPMs. So far I haven't been able to spot the problem and I'm hoping some of you might have some suggestions.

Attached: Subwat msq, Subwat Quint msq, Subwat Quint datalog
elutionsdesign
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Re: Staged injection blues

Post by elutionsdesign »

I've done staged injection many times but I never knew you could fully transition to the secondaries in MS3, nice! I think the troubleshooting may require some input from Phil Tobin and company as I'm not certain how the pulsewidths are accounted for in the logs. Example, you have PW and PW2, Duty Cycle 1 and Duty Cycle 2 which typically corresponds to bank 1 and bank 2 of the mainboard injector drivers. Then you have sequential PW 1-4 for the MS3X drivers, all well and good, but I think (and I hope wrongly) that the PW and Duty Cycle 1 in case of sequential actually reports the average of sequential PW 1-4 so as to be somewhat redundant. Certainly in your logs the PW value matches the values for sequential PW 1-4 and there is a Duty Cycle 1 AND PW2 and Duty Cycle 2 are zero because you haven't reached the staging values yet. Does that mean that INJ1 on the mainboard is supplying fuel? If so that would be the problem you're having, if not and it's just reporting the redundant average mentioned above then it's kind of useless to help you tune the transition. Did I make any sense?
Graduate of EFI University.

I build, repair, install and tune Megasquirt systems in North Dakota and beyond!
Subwat
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Re: Staged injection blues

Post by Subwat »

Thanks elutionsdesign, what you posted was helpful. This is my first attempt at staged injection. I know what I want to accomplish, but I'm trying to figure out how to do it. You're observation that mainboard INJ1 appears to be supplying the fuel is exactly the way the engine is acting. When I ran the upstream injector (INJ1) alone, not only did I have MS3X INJ 1-4 off in TS, I pulled the injector fuses, so that sneaky computer couldn't trick me, lol. Now I can't pull any fuses and the computer got me (meaning I don't know how to program it yet to do what I want).
Subwat
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Re: Staged injection blues

Post by Subwat »

Here are the latest developments, so any of you following can learn as I do:

I contacted Matt Cramer (DIYAutoTune) and he suggested I upgrade my firmware from 1.4.0 to 1.4.1, which I did, but there was no improvement.

I contacted EFI Analytics and got the following reply:

"Unfortunately when it comes to hardware setup, tuning support, and firmware functionality there is little I can do to help. I have never used staged injection and we do not right the firmware so I do not know how it is intended to work or how to set it up either. Tuning and hardware support are supposed to be handled by the ECU dealer that you purchased yours from but it sounds like you already tried them. I would say you need to try and get James Murry to chime in on the forum, he is the firmware developer and should be able to give you the best info on how that feature is suppose to work and be setup."
Brian H
EFI Analytics, Inc
support@efianalytics.com

Matt has now asked: "Does the second stage fire OK in output test mode?"

As soon as I get a chance, I'll see what I can learn with this test. However I'm wondering if I might need to set a higher RPM transition point and I may experiment with that.
jsmcortina
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Re: Staged injection blues

Post by jsmcortina »

What exactly is your question?

I tested your MSQ on the bench and at cranking RPMs only the primary sequential injectors are operating.

James
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Subwat
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Re: Staged injection blues

Post by Subwat »

James, when I first posted, I couldn't get the engine to idle (although the same tune without staging ran fine). Since then, I tuned the idle VE and idle advance timing tables and the engine starts and idles fine, however when I press the gas, the engine dies. It acts like INJ 1-4 get dropped as soon as the idle tables get dropped. The car runs fine (non-staged) on MS3X INJ 1-4 (my daily driver) but when I try the same tune staged, I can't get it to run. The single injector (V3 bank 1) runs great on the highway, but won't idle stably or run well at low RPMs. The engine acts as if it's trying to run staged as soon as it comes off idle.

Let me know what else you need to know. Thanks, Bob
Subwat
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Re: Staged injection blues

Post by Subwat »

2016-06-03_14.45.24.msl
2016-06-06_18.15.26.msq staged tune.msq
Attached is my latest MSQ and data log
jsmcortina
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Re: Staged injection blues

Post by jsmcortina »

I'm not seeing anything of note.

For comparison, disable staging. Start datalogging. Start the engine and bring it to idle where the problem would occur. Stop the engine and datalog.

Then, enable staging. Start datalogging. Start the engine and bring it to where the engine is running badly. Stop the engine and datalog.

Now, look at the two datalogs and see what is different.

James
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Subwat
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Re: Staged injection blues

Post by Subwat »

Thanks James, I'll do that.
Subwat
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Re: Staged injection blues

Post by Subwat »

2016-06-11_17.41.58.msl
2016-06-19_14.33.40.msl
2016-06-21_16.56.22.msq staged tune.msq
I'm still getting the same result when I enable staging. When not staged (running on MS3X INJ 1-4) engine runs fine. When staged, it starts and idles fine, but if I touch the throttle, it dies. I can keep it running if I give it a lot of throttle, but it is very erratic.

Looking at my data log unstaged ( running on: Seq INJ 1-4) shows: PW and PW2 show the same pulse width, which is also the same (or nearly the same) as Seq INJ 1-4. I believe PW and PW2 in this case show the average pw for INJ 1-4.

Data log for staging enabled (while idling) shows: PW2 is 0, PW shows same pw as INJ 1-4. Why is this? PW should also be 0 since the main board injector (bank 1) is not staged. When I give it enough throttle to keep it running (TPS about 12) PW and INJ 1-4 show equal pw but the AFR reads 19.9. By giving it more throttle (TPS 37) I can only get the engine to rev to 2300 RPM (no load) AFR 19.9, PW cycles rapidly from 2 to 9 and back, INJ 1-4 cycle similarly.

So far, I can't determine if I'm making an error in my set-up or if the code can't support what I'm trying to do. My next move will be to try to do this using a dual fuel tune.
Subwat
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Re: Staged injection blues

Post by Subwat »

I might be making progress, I disabled Secondary Fuel Load in General Settings. The engine now runs properly below staging RPM (on Seq INJ 1-4). However when it gets to staging RPM, it appears the upstream injector is not firing. The engine won't take a load and the AFR goes to 19.9. Seq INJ 1-4 show a reduced pulse width (which is correct) PW shows an increased pulse width (which is correct) but PW was showing a pulse width below staging that matched INJ 1-4. It should have shown a pulse width of '0' below staging RPM. Note that with my non-staged tune (Seq INJ 1-4) PW and PW2 show the same pulse width as INJ 1-4, even though they are not firing any injector, so in some cases, what the Log shows and what the ECU is doing is not the same thing.

It looks like the upstresm injector is not firing even though PW and Duty Cycle 1 show that it should be. I tested the upstream injector in output test mode and it did not fire with the staged tune. However I switched to my single injector tune, and the upstream injector fired correctly, so nothing wrong with the hardware.

I had thought that the Secondary Fuel Load was what the staged injector was supposed to use. It will work fine on the same VE table that INJ 1-4 use, but the ECU has to fire it.
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Re: Staged injection blues

Post by jsmcortina »

Subwat wrote:Data log for staging enabled (while idling) shows: PW2 is 0, PW shows same pw as INJ 1-4. Why is this? PW should also be 0 since the main board injector (bank 1) is not staged.
No, that's correct. PW is for the primaries. PW2 is for the secondaries.

I tried your old tune on the bench before and didn't observe any problems.

James
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Subwat
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Re: Staged injection blues

Post by Subwat »

2016-07-04_13.50.57.msl
2016-07-04_14.37.40.msq staged tune.msq
Thanks James, I thought there must be something wrong with the original tune and started messing around. I went back to the original tune and my data log agrees with Jame's bench test. But the AFR reads 19.9 when RPMs are in staging range -- the staged injector isn't firing. I tested the staged injector in testmodes and it doesn't fire, confirming the AFR reading and the fact that the engine won't rev-up once it gets to staging. The ECU thinks it's firing the staged injector, but it obviously hasn't found the staged injector. I need to find a way to introduce my ECU to my staged injector.
jsmcortina
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Re: Staged injection blues

Post by jsmcortina »

If the injector won't work in test mode, it isn't going to work any other time either.

James
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Subwat
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Re: Staged injection blues

Post by Subwat »

I've been learning that the hard way. But if I can't get it to fire (testmode) in the staged tune, there's something wrong with my tune. The ECU fires that injector fine when it's the primary injector -- won't fire it when it's the secondary.
Subwat
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Re: Staged injection blues

Post by Subwat »

I updated my software (Tuner Studio and Java).
In Testmode I tested the staged injector on V3, it didn't fire.
On MS3X I wired the outputs from INJ EFGH together and connected that to the staged injector, it did fire.
Note that the ECU is going to fire EFGH sequentially (same as ABCD) so I had to connect the outputs together to get the injector to fire 4 times per engine cycle.
My conclusion: the code doesn't support using MS3X for the primaries and V3 for the secondaries.
Result: I was able to get the engine to run and I was able to get it to transition to the secondaries, but it was very erratic and barely drive-able.
To ensure my settings in TS were correct and that TS was handling the tune correctly, I made the following test: I disabled Staged Injection, my tune was now identical with my daily driver tune (SEQ INJ 1-4 on MS3X) The engine ran correctly (the way it always runs on this tune). I then enabled Staged Injection, the engine was erratic (this is in the range below where staging begins). Note that I've had this problem from the beginning but only now have I been able to be certain what the cause is.
My conclusion there's a code/software problem, since the primaries should run the same on the same tune below staging.

I would appreciate any comments and please correct me If you see any error I might have made.
Matt Cramer
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Re: Staged injection blues

Post by Matt Cramer »

The code should allow using the main board injectors in this case - what firmware are you running?
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Subwat
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Re: Staged injection blues

Post by Subwat »

Firmware is MS3 1.4.1
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