Engine 92 mustang rough cold start


New Member
Mar 27, 2018
Ill start my 92 after it sits overnight and it will fluctuate between almost stalling n 1200 rpms. If i rest my foot on pedal for a minute its good after i let off after a minute.. Today though it idled at about 600 rpms on the verge of stalling. Then i let it warm up n it was fine. Idle at 900 rpms n no issues. Is something dirty or what? I was watching voltage for battery n it was moving alot a little lower then half then a little higher but never steady. Its 130 amp w underdrive pulleys. Thanks
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
polk county florida
On the fox tech page there is a forum technical/how to section, there you will find the 'surging idle checklist' go through it step by step and it will help you resolve your issue, save you time and money.
jrichker put it together and it works, just don't skip around, the next step depends on the results from the one before. I can tell you it works.


StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
Dublin GA
Some extra help to get you there...

You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the [URL=" http://forums.stangnet.com/showthread.php?t=698148"]Surging Idle Checklist[/URL]. 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. :D

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 250,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
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