Hello,
iam from Germany and i bought me an 1994 Ford F350 5.8.
Now i have some problems with the idle speed of the motor...
The idle speed is about 2000 upm and doesn`t go down.
I change the Idle Air control Valve, but the problem is the same again.

Please help me that i find the mistake...

Best regards
Sascha

 

Have you checked the timing?

 

Check the Throttle Position Sensor (TPS) and check the engine for vacuum leaks.
Also check for a sticking throttle or throttle and speed control cables.

 

Thanks for the help!
But what do you mean with timing???
Please give me some more information...

Best regards

 

Hi sascha76, To check your timing is to see if the ignition is firing at the correct time. This is done wth a timing light that is hooked up to the #1 cylinder of your motor and you aim the light at the harmonic balance pully (behind the cooling fan) to see where the timing mark is on the pully in relation to the gage (marked in degrees) located at the pully. It is a arrpw shaped pointer. You loosen the distributor bolt on top of the engine block at the base of the distributor shaft and turn the distributor to cause the timing mark to change as well as the idle speed of the motor. If you do not have a timing light or cannot locate one; you can adjust the idle by turning the distributor and just listen to the motor while it is running...Be careful because you can make the situation worse if you don't know what you are doing. I would look for vacuum leaks first before you start messing with the timing.....Good luck and keep me posted as to your progress. Listen to everyone in these posts. What one person thinks may be your problem may be the wrong issue acording to others..There are a lot of knowledgable people in here.

 

Have a hand helded mechanic ( check codes ) done to eliminate most electrical problems.The check for mechanicals. Sensors can be expensive just to find out the throttle cable was binding up.

Good luck!! and welcome to FTE!!
Later, Dennis

 

Check for vacuum leaks first. Check all the vacuum pipes around the engine for breaks or cracks and check the crankcase vent pipe for cracked elbows. An easy way is to spray carb cleaner around with engine running and listen for a change in engine note.
If all that is OK go to fordfuelinjection.com to see how to test the Throttle Position Sensor (TPS) and how to pull the error codes.

 

you left out the most important thing: removing the spout.

if you try it without doing that you will really screw up things.




get a manual is my suggestion.

 

Now i change the throttlepositionsensor and the idlespeed is well !!!

Thanks to all for your help!!!

Best regards

Sascha

 

Glad to hear your issue is straightened out. ........Looks like Lazy K was right about the TPS......Drive it like you stole it................