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Engine Idle fussy only when 1st starting

  • Thread starter Thread starter ggradtech
  • Start date Start date Apr 10, 2020
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ggradtech

Active Member
Jun 17, 2016
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Apr 10, 2020
#1
  • Apr 10, 2020
  • #1
When I 1st start my car (cold/warm, doesn’t matter), I need to feather the throttle a bit to get my idle to settle and stop surging. Once I get it manually “smoothed out”, I don’t have any more problems with surging or stalling. It’s just that “initial startup“ that gets the idle all wonky. I looked over the “idle“ sticky about 100 times. I can’t find the answer there. I was thinking of trying the IAC adjusting plate mod thing that I found info on. It’s a Ford part. Any thoughts?
 

General karthief

wonder how much it would cost to ship you a pair
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Apr 10, 2020
#2
  • Apr 10, 2020
  • #2
Bandaid. Go back over the list, take notes.
 

Steel1

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Aug 18, 2017
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#3
  • Apr 11, 2020
  • #3
Are you still running the stock ecu ?
 
G

ggradtech

Active Member
Jun 17, 2016
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Apr 11, 2020
#4
  • Apr 11, 2020
  • #4
Stock ECU. My timing was at about 9*. I set it at about 13-14 now. Idle is smoother, but when the AC is on, it will sometimes stall when 1st started up.
 

Steel1

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Aug 18, 2017
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Apr 11, 2020
#5
  • Apr 11, 2020
  • #5
Just thinking if it was a aftermarket ecu you could tune the wue to smooth it out.
Sure someone will chime in on the A/C issue.
 

jrichker

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#6
  • Apr 11, 2020
  • #6
What codes did you get when you dumped the codes?

Dump codes sticky

Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. Codes may be present even if the CEL (Check Engine Light) isn’t on. You don’t need a code reader or scanner – all you need is a paper clip, or if your lady friend has a hair pin, that will do the job.
I highly suggest that you read it and follow the instructions to dump the codes. http://www.stangnet.com/mustang-forums/threads/how-to-pull-codes-from-eec4.889006/
 
G

ggradtech

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Jun 17, 2016
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Apr 16, 2020
#7
  • Apr 16, 2020
  • #7
Probably a stupid question........ it seems my IAC valve is a 302 version. I have a 351 (95 Lightning) in my car. I see that there is a different model IAC used on the 351. Would changing the IAC to a 351 style make any difference? As far as codes go, I will need to buy a scanner. I don’t think counting flashes is for me.
 

Steel1

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#8
  • Apr 16, 2020
  • #8
Shouldn't make any difference,
I used the IAC off my 302 for my 393.
 
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