idling problem

[eugenewilhelmjr]

my 5.0 the idle keeps jumping up and down, runs stable at 1,200 rpm but when I try to lower it it starts to jump up and down what can I do to fix it, I set the timing, adjusted voltige regulator to .98 and still wont idle loike it should

 

[Blown88GT]

EEC controls idle. Hunting idle can be due to dirty or faulty IAC, Idle Air Control valve.

BTW, you did not set the voltage regulator to .98V, it's the TPS. Adjusting it has no effect on idle.

 

[5.0Droptop]

Dirty/ corroded pins in the salt and pepper shakers can cause idle isses also

 

[5.0Droptop]

Look up the tech articles for setting base idle and tps

 

[jrichker]

See the "Surging Idle Checklist for help with all your idle/stall problems. You can guess at the problem and throw parts at it, or you can use the checklist to help you find the problem quickly and inexpensively.

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.

 

[marine_80]

EEC controls idle. Hunting idle can be due to dirty or faulty IAC, Idle Air Control valve.

BTW, you did not set the voltage regulator to .98V, it's the TPS. Adjusting it has no effect on idle.

Fixed mine when i replaced it....

 

[vertvert]

my 5.0 the idle keeps jumping up and down, runs stable at 1,200 rpm but when I try to lower it it starts to jump up and down what can I do to fix it, I set the timing, adjusted voltige regulator to .98 and still wont idle loike it should

Really? Did you adjust your VR to .98 or your tps to .98 cuz just incase you didn't know your voltage regulator isn't adjustable and has nothing to do with your idle. So either ask "uncle jessie" to refill your headlight fluid or see if "daisy" can calibrate your knifilin pin. Or just sell the fox and buy a honda.

 

[eugenewilhelmjr]

Dirty/ corroded pins in the salt and pepper shakers can cause idle isses also

what are salt and pepper shakers

 

[eugenewilhelmjr]

Really? Did you adjust your VR to .98 or your tps to .98 cuz just incase you didn't know your voltage regulator isn't adjustable and has nothing to do with your idle. So either ask "uncle jessie" to refill your headlight fluid or see if "daisy" can calibrate your knifilin pin. Or just sell the fox and buy a honda.

hey man theres no need to be an a hole Im the one that built this car from scrap, Im good with mechanical issues just not good whith stuff like this

 

[jrichker]

Do the "Surging Idle Checklist , it will help you find and fix the problem easier.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car.

 

[5.0Droptop]

what are salt and pepper shakers

Sorry that's just what they are referred to as. Behind the upper intake you will see a black and white set of connectors we call the the salt and pepper shakers.

 

[jrichker]

Here's a picture...

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 Mustang FAQ - Wiring & Engine Info Everyone should bookmark this site.

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

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

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

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

 

[eugenewilhelmjr]

EEC controls idle. Hunting idle can be due to dirty or faulty IAC, Idle Air Control valve.

BTW, you did not set the voltage regulator to .98V, it's the TPS. Adjusting it has no effect on idle.

I replace this part and still idle jumps up and down

 

[eugenewilhelmjr]

Sorry that's just what they are referred to as. Behind the upper intake you will see a black and white set of connectors we call the the salt and pepper shakers.

my car does not have salt and pepper shakers because changed wiring harness from painless

 

[jrichker]

my car does not have salt and pepper shakers because changed wiring harness from painless

All the more reason to do the checklist link I posted.

 

[foxbodymike87]

EEC controls idle. Hunting idle can be due to dirty or faulty IAC, Idle Air Control valve.

BTW, you did not set the voltage regulator to .98V, it's the TPS. Adjusting it has no effect on idle.

umm??ive ajusted mine and it absolutely changed the idle.

 

[eugenewilhelmjr]

umm??ive ajusted mine and it absolutely changed the idle.

adjusted iac how

 

[4rdnut]

What did you set your timing at.