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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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My idle is rock solid except when.....

  • Thread starter Thread starter Methodical
  • Start date Start date May 20, 2006

Methodical

15 Year Member
Dec 1, 2003
1,192
11
59
Clinton, MD
May 20, 2006
#1
  • May 20, 2006
  • #1
I turn on the AC. I've done all of the idle setting of the TB scalar etc and changing the idle airflow values - that's how I got solid 800rpms. I kinda remember reading one of Grady's post that he thought that the "Battery Offset" would or could be an issue when it comes to AC. What can I do to get the AC to work without driving my idle crazy? Funny when in the past I switch to the stock tune, the AC work with no issues . Go figure.

Anyone else have this issue? If so what did you do to correct the issue.

Note: I have no problems at night with the lights on and the heater on.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
May 20, 2006
#2
  • May 20, 2006
  • #2
See if your K's take off in one direction or the other when AC is envoked.

If so, your offsets need tweecing.

Grady
 

zenboy99

Founding Member
May 12, 2002
2,212
0
47
Madison, WI
May 20, 2006
#3
  • May 20, 2006
  • #3
Does the EEC change idle parameters when there's a load at idle? Such as turning the steering wheel, putting AC on etc? I thought I remember my friends with Fox's saying a pro tuner changed that value (just shot them an e-mail).

Every morning I slowly back out of my driveway, my car wants to die when I turn the wheel. It seems my car idles fine, but that idle isn't very strong.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
May 20, 2006
#4
  • May 20, 2006
  • #4
There isnt any compensation for PS AFAIK (or brake lights). These are both commonly compensated for on 4 bangers, but Ford deemed us to have enough oomph to not need it.

Chad, the idle will bog when cranking the wheel if you are going real slow because there aint nothing helping it out.

The AC definately has compensation.

Grady, if you disagree with anything I said, feel free to set me straight.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
May 20, 2006
#5
  • May 20, 2006
  • #5
HISSIN50 said:
There isnt any compensation for PS AFAIK (or brake lights). These are both commonly compensated for on 4 bangers, but Ford deemed us to have enough oomph to not need it.

Chad, the idle will bog when cranking the wheel if you are going real slow because there aint nothing helping it out.

The AC definately has compensation.

Grady, if you disagree with anything I said, feel free to set me straight.
Click to expand...

NO JT

I would not disagree

Maybe

If you had a heavy load from several of the kind of accessories that pull lots of juice from the batt

And

The adaptive was really cranking in or out a lotta fuel

Then maybe ... just maybe

The load from the ps working hard might pull you over the line to where the isc/pcm could not recover and ... you stall

If one had his Tweecer fired up
and
datalogging
and
capturing to hard drive

he'd have the hard data to show plainly what was a goin on

Grady
 

Methodical

15 Year Member
Dec 1, 2003
1,192
11
59
Clinton, MD
May 20, 2006
#6
  • May 20, 2006
  • #6
I will have to check things out. I haven't datalogged in awhile. I plan to datalog today because I have to go into the office. Thanks
 

Methodical

15 Year Member
Dec 1, 2003
1,192
11
59
Clinton, MD
Jun 4, 2006
#7
  • Jun 4, 2006
  • #7
OK. An update. I think I found out what was causing my idle problems with the AC on. The system was low on refrigerant which causes the compressor to constantly kick on and off, which reaked havoc on the EEC and idle. When I charge the system, the compressor now stays on and idle is fine. Just a little insight just in case someone else goes thru this.
 

zenboy99

Founding Member
May 12, 2002
2,212
0
47
Madison, WI
Jun 5, 2006
#8
  • Jun 5, 2006
  • #8
Thanks for posting your solution. It always helps for those that use the search function for their problems
 

Methodical

15 Year Member
Dec 1, 2003
1,192
11
59
Clinton, MD
Jun 6, 2006
#9
  • Jun 6, 2006
  • #9
zenboy99 said:
Thanks for posting your solution. It always helps for those that use the search function for their problems
Click to expand...

No problem. I wished others would do the same instead of leaving the poseters hanging and the searchers also.
 
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