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Idle Surging Problems

  • Thread starter Thread starter Foxybody95
  • Start date Start date Sep 19, 2015
  • Tags Tags
    a9l idle no throttle response sct chip sluggish surge
F

Foxybody95

Member
Sep 14, 2015
90
3
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Sep 19, 2015
#1
  • Sep 19, 2015
  • #1
Hey guys me again, It seems I cant keep go a single week without a major issue coming up on this thing so here's the deal now. I fixed the break up issue I talked about before with a new distributor but the car still wont idle. I have an a9l and an sct chip and I'm starting to believe I have a computer problem when you start the car it usually idles very high somewhere around 12-1300. Now if you let it sit the idle will start to surge slowly then gain momentum until it eventually kills the motor. It is also seeming very sluggish and i hope the two problems are related. Now If I pull the spout the idle drops to 900 which is exactly where my tuner set it at for my cammed motor. Fuel pressure seems good its around 36 at idle and 42 at WOT and its no longer breaking up or misfiring. What could be the cause?
 

mikestang63

SN Certified Technician
Aug 27, 2012
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In the garage
Sep 19, 2015
#2
  • Sep 19, 2015
  • #2
take the chip out. do a base idle reset
 
F

Foxybody95

Member
Sep 14, 2015
90
3
8
Sep 19, 2015
#3
  • Sep 19, 2015
  • #3
How do I reset the idle? and would that be a reason its being sluggish?
 
F

Foxybody95

Member
Sep 14, 2015
90
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Sep 20, 2015
#4
  • Sep 20, 2015
  • #4
The idle is reset still idles high even tho i set it at 900 still surges was even surging slightly as i set the idle made it a pain in the but
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Sep 20, 2015
#5
  • Sep 20, 2015
  • #5
how did you reset the idle. did you disconnect the IAC and turn the idle screw all the way out until it reaches the lowest rpm that you can idle and then reconnect the IAC.
 
F

Foxybody95

Member
Sep 14, 2015
90
3
8
Sep 20, 2015
#6
  • Sep 20, 2015
  • #6
I just got it down to 900 and left it i couldnt get it to its lowest point the thing wouldnt stop surging long enough
 

jrichker

StangNet's favorite TOOL
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Mar 10, 2000
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Dublin GA
Sep 20, 2015
#7
  • Sep 20, 2015
  • #7
You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. It includes how to dump the computer codes quickly and simply as one of the first steps. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 159,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
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