engine dies at idle but runs while in drive.

[93 LX]

86 Speed Density 5.0L, Auto.

Some notes: Missing Sprout connector. Missing Vacuum Diagram.

Symptoms: Engine will start and run for several minutes. As idle comes down to a normal curb idle the engine will act like its being starved for fuel. It almost sounds like a vacuum leak but I do not hear any hissing. If car is shifted in to Drive or Reverse the eigine will continue to run. Confusing........

Things Tired: Visual of all hoses, found 1 with a screw inserted. Unknown where this one goes. Tried Sprout connector from 93 Stang with same results but ending idles at a higher rpm.

Any Ideas?

 

[jrichker]

Put the SPOUT back in. When the SPOUT is out, you have no spark advance. That kills both performance and economy. When the SPOUT is in, it advances the timing and that increases the idle speed.

You guys with idle 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 post has all the fixes, and steps through the how to find and fix you idle problems without spending a lot of time and money. 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!

Diagram courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel pump, alternator, ignition & A/C wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Computer, actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Fuse panel layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

 

[93 LX]

Thanks...

I have worked on MAF engines but am not sure how SD engines work.

Thanks again