Engine starts and warms up then shuts off?

1991 FORD F-150
200,000 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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TANDY L ARMSTRONG
  • MEMBER
  • 1 POST
Will restart and run for a short time then shuts off. At first this only happened in air temperatures below 65 degrees. Ran fine in temperatures above 65. Now it does it regardless of temperature.
Jul 12, 2023 at 8:24 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,249 POSTS
I have seen the IAC valve cause this issue, but it could be a vacuum leak as well, here are two guides to help us fix the problem and I have included the location of the IAC in the images below:

and use this guide when the engine is cold only:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.


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Jul 13, 2023 at 5:26 AM
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