The car doesn't want to catch itself at idle from higher RPM

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Originally Posted by mlecy

We tried using the data from the spreadsheet from FID but it didn't seem to work mustang_man. I think you might have told in a different post about not adjusting the MAF table to adjust the low slope data instead. So had been doing that and got it to run better using that. I just got that new FIC spreadsheet that does the calculations for you. I have not had a change to put the info of fuel pressure and AFR target in that one yet and update the tune with that info. I was planning on working on that tonight.

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I think you have mistaken me for somebody else, i would never tell anyone to scale the slopes. I always work with MAF unless their is a hard code like the 79-04 mustang have. then i scale everythng HI, Lo, engine, manifold, ect. hopefully you will get it figured out

Sorry mstang_man you are correct. You comment on that thread. It was iceman321 that told me to do that.

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Originally Posted by mlecy

So figured out something very odd tonight. So I put in those number from that spreadsheet using your tune you sent me as a base. It didn't like that and went into injector cut every time. I adjusted the low fuel number from about 315 where they were at up to about 450 in small increments. Nothing worked so I also went a little lower then 315 and that didn't work either. I went back to your tune just like you sent it to me that worked and that would not work. So I went to the tune you based that off of that I sent you. That would work. I raised the idle on that one to 950 and did the crankshaft position relearn and it worked. No that code just the MAF one just said permanent not current or pending. So I think that is done. But I had noticed that if I revved the car right away it would rev and be fine then the O2 sensors kick in and would do injector cut. So I did some experiments and if I keep it above 1500 until the O2 sensors kick in everything is fine no issues. Same tune if I don't do that I get injector cut. Now on the tune I sent you I don't have the issue I can just start it and let it idle and it will rev fine. But every odd. I do have a log of one time where I started I revved it with out issue let it drop and then all of a sudden the injector cut happens. I did notice that a couple times when I was messing with the fuel low that it would do that also.

Have you ever seen anything like that?

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I think you need to find a stock, unadjusted file, and start over.
Then apply the injector data from FID, estimated air flow differences for your Cam, and TB data from VMP

I'm seeing lots of modifications in this, from different opinions, and sometimes too many cooks spoil the stew.

This is your original base file with TB table changes, FID injector data (which now I understand might need PSI adjustments) Idle speed and airflow adjustments

ok. I will drop the PSI down to 42.5 from the 58 it is at now and we will see how it goes.

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Originally Posted by mlecy

ok. I will drop the PSI down to 42.5 from the 58 it is at now and we will see how it goes.

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I would run my fuel injector pressure drop at 39.15, and both Max allowed duty cycle to 2.0

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Originally Posted by mstang_man

I would run my fuel injector pressure drop at 39.15, and both Max allowed duty cycle to 2.0

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That 39.15 is what was stock, what does that do or represent?
(Not at all questioning you, just want to expand my knowledge.)

Thanks

The coyote uses inferred fuel rail pressure and manifold pressure (vacuum) to determine the total pressure drop. In theory you could have 58 psi rail pressure and -26 inches (-13 psi) vacuum under decel. This would make a total pressure drop of 71 psi (58+13=71). Most of the Ford racing data doesn't go this high, so it is accurate for steady state cruise and WOT, where the total pressure drop is within the range of the multipliers, but sometimes it causes inaccurate fuel during decel and transitions that involve a lot of vacuum.

This seems to be a bigger problem for some injectors than others. In particular, if the low slope and/or offset data is inadequate it affects a car with bigger injector more adversely because for a given amount of fuel flow a large injector will spend a greater proportion of its time in the low slope range than a small injector. this is why the Ford data for larger injectors is at 39.15 psi and works well.

So if I understand what you are saying even if you are running at 58 because of the pressure drop under decel you would leave the pressure at 39.15 in the tune?

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Originally Posted by mlecy

So if I understand what you are saying even if you are running at 58 because of the pressure drop under decel you would leave the pressure at 39.15 in the tune?

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Yup, even ID 850 i leave 39.15 on 4br

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Originally Posted by mstang_man

The coyote uses inferred fuel rail pressure and manifold pressure (vacuum) to determine the total pressure drop. In theory you could have 58 psi rail pressure and -26 inches (-13 psi) vacuum under decel. This would make a total pressure drop of 71 psi (58+13=71). Most of the Ford racing data doesn't go this high, so it is accurate for steady state cruise and WOT, where the total pressure drop is within the range of the multipliers, but sometimes it causes inaccurate fuel during decel and transitions that involve a lot of vacuum.

This seems to be a bigger problem for some injectors than others. In particular, if the low slope and/or offset data is inadequate it affects a car with bigger injector more adversely because for a given amount of fuel flow a large injector will spend a greater proportion of its time in the low slope range than a small injector. this is why the Ford data for larger injectors is at 39.15 psi and works well.

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But this is not a Coyote. More to say since it's a return style PCM no longer cares about pressure drop as from now on fuel regulator does that.

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Originally Posted by mstang_man

Yup, even ID 850 i leave 39.15 on 4br

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return style with ID 2000 is suggested to set base fuel pressure to 43.50, of course this isnt a coyote it was meant as a reference that fuel pressure along with other parameters can effect total pressure drop and the total pressure drop is within the range of the multipliers, but sometimes it causes inaccurate fuel during decel and transitions that involve a lot of vacuum. as example ID 850 on coyote i leave it at 39.15

the injector flow rates do not look anything like 2000 cc flow rates, use the manufacture data and zero in from there, i shouldn't need much adjustment depending on the fuel psi, worst ive seen is like 25+/- fuel trims but its not hard to adjust from there. also when trying to iron out the kinks you can set min throttle body angle to 2 or 3 deg and min corrections to -3 max +3 so you dont fall flat on your face.

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Originally Posted by iceman321

the injector flow rates do not look anything like 2000 cc flow rates, use the manufacture data and zero in from there, i shouldn't need much adjustment depending on the fuel psi, worst ive seen is like 25+/- fuel trims but its not hard to adjust from there. also when trying to iron out the kinks you can set min throttle body angle to 2 or 3 deg and min corrections to -3 max +3 so you dont fall flat on your face.

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Not sure I'm following your here...
You say 2000 cc flow rates, per MFG data, then adjust from there. Is that adjusting based on PSI? Fuel Trim data?
Are you manipulating MFG supplied data for tuning purposes?

Don't get me wrong I'm no Ford Guy. But I'm hearing you to say manipulate injector data to get AFR dialed???

Not sure which tune you are referencing here that don't look like 2000 cc injectors. But the last tune had MFG supplied data @ 42 PSI.
OP reached out to MFG to adjust for his 58 PSI return system.

Not trying to challenge you, I just don't understand your post.

Those are FID not FIC - they supply only a partial data to say the least so changing slopes to dial in is a good move.
This is a problem when you get cheap injectors with no data...you have to improvise. I learn in the process you better
change injector data first if you have a good known MAF curve. Best to use stock intake to verify this - until trims are close to 0.

Now he has a solid MAF curve for his JLT, enters a good injectors data and this should run at least Ok-ish...but it doesnt.

As far for injector data, only Injector Dynamic has relatively solid specs, fic, deatchwerks and others are not any good.

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Originally Posted by veeefour

Those are FID not FIC - they supply only a partial data to say the least so changing slopes to dial in is a good move.
This is a problem when you get cheap injectors with no data...you have to improvise. I learn in the process you better
change injector data first if you have a good known MAF curve. Best to use stock intake to verify this - until trims are close to 0.

Now he has a solid MAF curve for his JLT, enters a good injectors data and this should run at least Ok-ish...but it doesnt.

As far for injector data, only Injector Dynamic has relatively solid specs, fic, deatchwerks and others are not any good.

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I think I follow you...
You are saying if stock TB, Intake, and a previously fine tuned MAF sensor you can adjust your new (cheap) injectors based on fuel trims...

Now he has changed Intake, TB, Cam, Pulley, Headers, which all change airflow and MAF calibration.
So where do you start?

The OP has been told the injectors are the same "Base Bodies" as a well known companies injectors and its okay to use their data.
I sense you are saying this will be fair at best?

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Originally Posted by dhoagland

I think I follow you...
You are saying if stock TB, Intake, and a previously fine tuned MAF sensor you can adjust your new (cheap) injectors based on fuel trims...

Now he has changed Intake, TB, Cam, Pulley, Headers, which all change airflow and MAF calibration.
So where do you start?

The OP has been told the injectors are the same "Base Bodies" as a well known companies injectors and its okay to use their data.
I sense you are saying this will be fair at best?

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No, you don't follow, sorry m8.

All of this would affect airflow?: yes! Do you change MAF to address that?: no!

MAF curve is there to calibrate your sensor in a pipe not to fix your problems or changes in Volumetric Efficiency. If he has that much
of a change in VE he need an external MAP sensor to fix the issue...but then again what SD does while he has anticipation turned off.

We tried to fix this with MAF sure we did...turned out even worse. Every time you correct MAF even by a quarter of % car goes info fail mode.

BTW...I'm the one who's trying to remote tune his car...to no avail unfortunately. He has/had a bunch of issue with the car...
We solved a lot, not sure we still have any...or this is just another problem/s that remains to be seen...

There's is something very wrong with this car...hard to tell what this is.

I've tuned many Coyote and Trinities withbig injectors like 1700-2200cc and they all run ok-ish with few basic changes...just not this one.

The injectors are from Fuel Injector Development (FID). They are used by some of the no prep guys and some other racers. The only data they gave was for 42.5 psi. I bought them because had been told buy a few people they were top of the line ones. I was not waiting to get cheap ones or Chinese knock off ones. They were about 1400 for the set. After talking with them some I found out they are Bosch core in injectors. They had very close to the same data as the ID2000 ones. I sent the ID2000 spreadsheet to FID and he said those are basically the same injectors so I can use the ID2000 spreadsheet that can be adjusted for pressure and stoich valve.

Iceman we were trying some different things in those tunes. So that might not have been the actually data from the spreadsheet. As I had been in some of them trying to adjust the injector low slope to get it to lean out as it was running rich and having issues holding an idle.

In the Airflow -> Idle -> General

Enable Torque Decel Switch if it's disabled

In the Airflow -> Idle -> Torque

Double or triple the values in the Idle Torque Reserve tables
Lower the values by 50% in the Decel Torque tables below 3000 RPM


This helped my boosted coyote

Interesting. Thanks Shalva. I will check that out and give it a try.