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4 minutes ago, Ashley P said:

I thought you had a vacuum pump and could check it that way (eliminating the questionable hose)?

Well the problem is it is intermittent.....if it isn't acting up it doesn't do much good to test it.  All I can think of is it isn't always pinching off?

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Can you tee in your mechanical gauge to compare the electrical reading to?   And the same token, can you "tee in" a volt meter (like a Fluke with "min/max" memory) to compare to the readings your ECM "sees"?

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I have a couple other ports on the throttle body I could try (they all feed to below the throttle plates) and will do a comparo tonight vs a mech gauge.

I can't really tie in very easy without cutting into the harness (I might have to though).  I don't have anything with a min max setting.  I do have a little panel mount digital volt gauge I could wire in and tape on the windshield to compare with.

the Megasquirt 3 in the boxes of Fairlane parts is seeming more and more tempting....toss in a 3x board and make up a simple harness and plug it in and see if it does better

 

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ok so I think everything is working ok.  battery shows 14.x V with a meter....fast dashboard just shows different.

 

Seems the truck gets touchy when it gets around 200F.  I need to check to make sure it isn't pulling timing or fuel when it gets there.

 

So right now it idles good and pulls so so....but the cruise at 2,000 rpm is just a bunch of popping and if you coast it likes to backfire once it loads up.  So I am guessing I need to pull some fuel out at lower loads and higher RPM in the coast region.  any idea on where to start on the cruise tuning?

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Do you know how old your wideband O2 is?

What does your A/F table look like? How much overlap is in your cam?

If it's 0 or negativeoverlap it can cruise at 14.7.  If it has some overlap it will need to cruise around ~13.  It should go to ~12.5 where you make power (WOT area from 3000 and up)

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about 4 degrees lobe separation between exhaust closing (27 degrees) and intake opening (31 degrees).  Comp XFI 280 grind.

 

Wideband was used with the kit.  and Screw Comp for using something other than a nice and cheap VW wideband and going with a stupid pricey wideband sensor.

 

I attached a log and my tune if anyone wants to look at it.

3-27-17.log

new350 03 27 17.gct

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I am thinking the target Air/Fuel is too lean and is fighting me trying to richen it up.  Currently it is around 14.7:1 at cruise.  I am going to drop it a bit to 14.0 or 13.5 tonight (maybe just take 0.5 out of everything above idle) 

 

I think I have a rich spot in my deaccel (under 50% load in lower rpm) causing it to be fat (been concentrating more on my cruise tuning issues)  which is causing it to load up and give a good backfire if I coast for too long (don't think the neighborhood likes this) 

 

I am going to check these areas in my tune tonight and try and be ready for session on Wednesday.

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On decel, you can actually go to zero fuel because the motor doesn't require it to run.  So make it do what it needs to do to run at cruise.  Look at the graphical version to help weed out peaks and valleys.  Turning off O2 correction will help you tune cruise.  Just raise the enable rpm up to 4000 or so.

XFI actually has a firmware revision that closes the injectors on decel for guys that are looking to increase fuel mileage.  You don't want to physically set the bottom row to zero because it might mess up cruise, so they developed this firmware.

 

Look at timing for a backfire also.

 

I'll look at your tune on my laptop tonight and see if I see anything.

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Just now, Mike said:

 

I'll look at your tune on my laptop tonight and see if I see anything.

I am sure you will see a lot.

meme-i-have-no-idea-what-i-am-doing.png

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Yes, I'm not a pro either, but I might be able to find something to help you.  I knew the early FAST pretty well.  The XFI I had to struggle through a lot.

What about your Injector Offset versus voltage table?  Did you get actual data for your injectors or use what XFI already had in there?   That can have a huge effect on idle as your voltage fluctuates.  I imagine it could hurt light cruise also.  Here is a good starting point if your injectors are on that list.  http://documents.holley.com/techlibrary_injectorflowdatarev2.pdf

Also if you've done any firmware revisions and are working from an old file, you could have new tables that aren't filled in.

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I used what was there.  I am running some 42# ford motorsport ev6 injectors (I think GT500 injectors?)

I had a guy from FAST run me through firmware updates and some other troubleshooting to get the motor running on the crank trigger (turns out some wiring on the ignition plug had been jacked with before I got the harness)

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Yeah, you have to get the injector data right before anything else will work right fueling wise. And make sure it's in open loop!

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So I went to double check my injectors.  I had purchased a set of ford motorsport injectors for this project with EV6 connectors and I THOUGHT from memory they were 42's.....

 

20170328_192551_zpszc7lpoth.jpg

 

Interwebs seems to say these are 47's

https://performanceparts.ford.com/parts/ics/m-9593-lu47.pdf

Updated my injector offsets with this info.  So this should make a big difference if I was running a smaller than actual injector.  Updated my base tune back to the canned fuel mapping.  Turned off my closed loop also.  a little late here to fire it up and test drive it.  

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If the injector was bigger than you thought, it would be running richer than intended, and generally better than you're describing. But, offset and breakpoints make a huge difference, so that may really help the tune once that's set right.

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I think the issue is I was in closed loop and had a chunky curve that was pulling from a lower RPM (IDLE) area of the curve and then above I left alone so the average of the fields gives me a lean mixture.  Being a stick shift a little surging seems much worse once you get a little bucking.   I think it was close and just needed a little more (maybe just more at a higher RPM range so it has more to pull from)

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With it running in OL, you can just tune by Wideband and vacuum to get it dialed in. from idle-1500 or so you can adjust the map up or down until you get the best vacuum reading on the map. You'll have to adjust a lot of cells individually, but it goes fast. Then you can free rev it and hit some more of the low load rpm cells the same way. hold steady at 1200 or 1500 and adjust those cells. Once you see here those are at you can start driving a bit and getting the lower vacuum cells cleaned up. THIS TAKES A LOT OF TIME. You will be watching the WB while dialing in larger chucks of the map. You can adjust groups of cells up or down by a %-age instead of induvidual cells. ONce you get it all pretty close, then you can focus on single cells, or just interpolate. 

As always, only make fueling changes with the engine fully warmed up.

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I think my enrichment tapers off around 170F currently.  I might need to pull it down sooner though.

 

Temperature is one thing I am battling.  I know I need it up to tune without and trims or enrichment kicking in but my e-fans crapped out and new ones are not here until Monday.

 

If I am just making the big initial changes to get it drivable can I make those with the motor semi cold like 150-160F range?  I know I would likely have to dial them in more once warm.

 

Fingers crossed maybe I can get something that can actually drive without scaring children and pets.

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Try setting all your enrichment tables so that they are zero when you are tuning or wait until its warm enough that it isn't a problem.  These are fine tweak things.

I'm pretty sure I have the Steve Morris XFI training dvd.  I'll check tonight.  If I have it, I'll send it to you.  It's not the end all of training, but should get you thinking about a strategy for getting there.

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35 minutes ago, Mike said:

Try setting all your enrichment tables so that they are zero when you are tuning or wait until its warm enough that it isn't a problem.  These are fine tweak things.

I'm pretty sure I have the Steve Morris XFI training dvd.  I'll check tonight.  If I have it, I'll send it to you.  It's not the end all of training, but should get you thinking about a strategy for getting there.

That would be a huge help!

 

There is a EFI101 class in Seattle in June I have thought of signing up for.  I am just trying to justify the expense right now as I view it as something for a shop employee or racer to need....I just want my junk to run.

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1 hour ago, NukeWorker said:

Fingers crossed maybe I can get something that can actually drive without scaring children and pets.

But, isn't that the point??

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3 hours ago, Disney said:

I'd do the EFI101 class in a heartbeat.

I don't have baller Nissan monies

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