Idle Issues & ISCFLG

Anything not covered in the other forums.
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Idle Issues & ISCFLG

Unread post by Gary Lewis »

First, I apologize that I'm not using the same software you folks are, so truly do not speak the language. But I need a bit of help getting my idle sorted.

I've read, read, & re-read the instructions on fuel and idle, and have attempted to follow them. But I do run into the translation problem between BE and Ford function #'s, so may not have gotten everything perfect. However, I do have the fuel sorted, I think, but am now having problems with the idle.

The idle is smooth enough, but I cannot get it down to the 648 RPM I want. Instead it runs about 800 when fully warmed up. But I'm not getting the ECU to control the idle RPM as ISCFLG is staying at 0, meaning I'm in Dashpot Preposition.

So I'm trying to figure out how ISCFlG gets set. In BE-speak one hurdle that has to be jumped is Lower Limit to Enter Dashpot RPM Control, and that is set to .4 LBS/MIN in YER2. However my AM is running ~1.2 at idle, so I know I'm not in the range to go into RPM Control.

As said, I've gone through the Idle writeup many times and it looks like an AM of 1.2 at idle is reasonable. So can I just set the lower limit to something like 1.4 to enter RPM Control?
decipha
Posts: 4955
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: Idle Issues & ISCFLG

Unread post by decipha »

if your stuck in dashpot then your either not setting the closed throttle flag or you did something to prevent dashpot from decaying out.
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Re: Idle Issues & ISCFLG

Unread post by Gary Lewis »

Ok, I'll explore that. Thanks.

I did go ahead and set the lower limit to 1.4 and drove it. ISCFLG stayed at 0 in spite of the AM getting down to 1.2 or less. So I never went into controlled RPM.

So I'll explore the closed throttle flag first and then check out the dashpot decay.

By the way, I'm not getting email notification of responses, but I have subscribed. And there's nothing from here in spam. Any ideas?
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Re: Idle Issues & ISCFLG

Unread post by Gary Lewis »

A quick look at the log shows APT at 0 save for when it went to 1 as I ran it at WOT. So you were right with the first thought, and now I'm looking for why it isn't going into closed throttle. Any suggestions? I'm reading your writeups....
decipha
Posts: 4955
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: Idle Issues & ISCFLG

Unread post by decipha »

rativ may be holding you if all checks out

thats the maximum closed throttle tps voltage usually around 1.25 volts or so. You can kick it up to 1.5 volts as I always do.
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Re: Idle Issues & ISCFLG

Unread post by Gary Lewis »

Yes, I saw that in your writeups. But while it is set at 1.22v my TPS voltage is lower than that, usually about 1.09v. And I checked all of the other parameters you suggested, to no avail.

HOWEVER, I got worried that APT had never gone to -1 so pulled up some old logs and discovered that it was working fine up until one month ago today. In the first log of May 7th it didn't work, and apparently hasn't since. So I'm comparing the previous tune to that tune to see what changed and I should be good to go.

So thank you very much, you pointed me in the right direction. THANKS!
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Re: Idle Issues & ISCFLG

Unread post by Gary Lewis »

Decipha - I found something. The last time APT went to -1 RATCH was at apparently at 1.07, which I'm inferring as TP was 1.1 and TP_REL was .03. The next log had TP at 1.1 and TP_REL = .8 so RATCH must have been .3. What could cause that? And might that cause it to not set APT to -1?
Gary Lewis
Posts: 25
Joined: 2022 May 24, 17:10
Location: Skiatook, OK
Vehicle Information: 1985 F250 w/a Scotty-built 460, EEC-V, ZF5, etc. No EGR or cannister purge.

ECU is a YAZ3/ML1-441 & I'm using AGANN/YER2. Programmed via BE & MongoosePro Ford.

Re: Idle Issues & ISCFLG

Unread post by Gary Lewis »

Well, it is fixed!

I'm not exactly sure I know what the problem WAS, but I disconnected the battery for 10 minutes and then it started up and the throttle shows as "closed". I'm guessing that when I adjusted the throttle stop screw RATCH didn't change. And while I did disconnect the TPS and started the truck up to reset it as per the instructions, it didn't solve the problem. But disconnecting the battery did the trick.

Now to tidy things up just a bit and enjoy the truck!
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