SPONSORED LINKS

1991 Ford F-150 engine idle speed

Tiny
NBCSTUDENT2006
  • MEMBER
  • 1991 FORD F-150
Engine Performance problem
1991 Ford F150 V8 Four Wheel Drive Manual

I had a problem with my idle speed and changed my tps this changed nothing so as the engine was running I unplugged the idle air control valve and the rpm's dropped to normal so I figured this was the problem so I changed it as well ad the enging still idles high so I unplugged the new idle air control valve any ideas what this might be?
SPONSORED LINKS
Thursday, April 29th, 2010 AT 2:27 PM

1 Reply

Tiny
MERLIN2021
  • MECHANIC
  • 17,250 POSTS
Check the cable and if it has cruise control check that cable too. Remove the cables, operate throttle by hand, if it returns to normal, one of the cables is bad. Or You may have a vacuum leak, get a can of spray Throttle body cleaner, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs!
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
-1
Thursday, April 29th, 2010 AT 2:50 PM

Please login or register to post a reply.

Related Idle Air Control Content

Clean Idle Air Control Ford Super Duty 5.4L
VIDEO
Clean Idle Air Control Ford Super Duty 5.4L
Instructional repair video
Idle Air Control Valve Service
GUIDE
Idle Air Control Valve Service
The idle air control valve is responsible for controlling the engine idle speed via the car's PCM (computer). These valves are configured differently depending on...
VIEW MORE

Sponsored links