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Engine '90 LX 5.0 engine stall after running awhile and coming to an idle

  • Thread starter Thread starter FOX90LX
  • Start date Start date May 25, 2021

FOX90LX

New Member
May 25, 2021
2
0
1
Washington
May 25, 2021
#1
  • May 25, 2021
  • #1
I have a 90 LX 5.0 convertible that stalls after running awhile and coming to an idle. It starts up again but seems to struggle for voltage as it turns over slowly. When it stalls, it is as if it loses fuel feed. It starts quickly when cold and runs/idles like a clock. The engine has good throttle response. The issue happens after it is up to operating temperature. I have not attempted any fixes yet.

It has a cold air intake, GT40 heads and intake manifold. It is an AOD transmission with a shift kit I believe as it shifts well above the stock shift points of 2-3k rpm. I bought the car with these mods already done. The odometer is +200k miles. I do not abuse it. Mostly throttle it around from golf course to golf course and smoking cigars I am not a mechanic but I am mechanically inclined and plan to do a T5 swap soon and SN95 axle upgrade.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
May 25, 2021
#2
  • May 25, 2021
  • #2
Check your fuel pressure after warm up.
Check for codes.
The 5.0 tech thread has some procedures for this.
Let us know what you find.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,265
17,952
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Massachusetts
May 25, 2021
#3
  • May 25, 2021
  • #3
You need to check fuel pressure and codes, I have some suspicions but it's too much to throw out every possibility so we need to narrow it down first.
 
Reactions: General karthief

FOX90LX

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May 25, 2021
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Washington
May 25, 2021
#4
  • May 25, 2021
  • #4
See attached. Missing anything?
 

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