Fires up but won't stay running

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h82crash
MS/Extra Newbie
Posts: 10
Joined: Sun Jan 18, 2015 9:47 pm

Fires up but won't stay running

Post by h82crash »

I have a Ford 5.0 Windsor, stock except for 50mm ITBs. Another person with a 408 with ITBs did not have good luck with ITB Mode so he runs alpha-n primary with SD secondary VE tables and suggested I try it. That's the background why I haven't tried ITB mode yet. I don't believe I am to a point where that matters, anyway.

I hit the starter and she fires but dies immediately. I increased the ASE and it didn't do much. Created a new VE table increased WUE and goes for maybe 1-1.5 seconds and quits. Running MS2/extra 3.3.3 with Ford TFI.

This msq has the primary tables TS generated.
2015-02-06_18.40.59.msq
The data log..
2015-02-06_18.25.27.msl
Most recent with richer VE table and ASE/WUE
2015-02-07_08.21.56.msq
Tks.
Factory Five Roadster, 5.0 Windsor, 8-stack injection, MS2/Extra, Levy/Astro Super Alloy T5, 3.27 LSD IRS.
elutionsdesign
Super MS/Extra'er
Posts: 1341
Joined: Mon Sep 05, 2011 1:20 pm

Re: Fires up but won't stay running

Post by elutionsdesign »

Yeah, I think it may matter, when it transitions from "cranking" to "run" the PW2 is actually dropping to zero briefly. Then of course as its dying it kicks back on to the cranking pulse width. I'd first go into the cranking settings and set your cranking rpm lower, maybe 400 or so, 650 is kind of high. Then I would change to ITB mode and run only one VE table. I have tuned ITB/turbo cars with the scheme you're trying but with a N/A car its a bit backwards from what you should be doing and ITB mode does that. SD until you reach a MAP value where fueling resolution is poor, then Alpha-N where it has better fueling resolution.
Graduate of EFI University.

I build, repair, install and tune Megasquirt systems in North Dakota and beyond!
h82crash
MS/Extra Newbie
Posts: 10
Joined: Sun Jan 18, 2015 9:47 pm

Re: Fires up but won't stay running

Post by h82crash »

Thank you. Got it going. It's rich at idle and dies when I hit the throttle at any rate but extremely slow. Manual says not to worry about accel enrich until VE table is good. I need help to at least get it drivable so I can start tuning. I forgot to add, not running an IACV. Here are my latest parameters and log. Thanks in advance.
Idle rich.zip
2015-02-08_18.35.22.msq
Factory Five Roadster, 5.0 Windsor, 8-stack injection, MS2/Extra, Levy/Astro Super Alloy T5, 3.27 LSD IRS.
elutionsdesign
Super MS/Extra'er
Posts: 1341
Joined: Mon Sep 05, 2011 1:20 pm

Re: Fires up but won't stay running

Post by elutionsdesign »

Try this.
Graduate of EFI University.

I build, repair, install and tune Megasquirt systems in North Dakota and beyond!
h82crash
MS/Extra Newbie
Posts: 10
Joined: Sun Jan 18, 2015 9:47 pm

Re: Fires up but won't stay running

Post by h82crash »

Thanks a bunch! That improved things greatly but I just couldn't get rid of the stumble right as the butterflies open so I added MAPdot and that was the trick. The throttle response at zero load is nice. Next, take her for a drive. :yeah!:
Factory Five Roadster, 5.0 Windsor, 8-stack injection, MS2/Extra, Levy/Astro Super Alloy T5, 3.27 LSD IRS.
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