1987 5.0 EECIV IAC question
Thread Starter
|
Mountain Pass
Joined: Feb 2023
Posts: 131
Likes: 17
From: Binghamton NY
1987 5.0 EECIV IAC question
'87 F150 EECIV 5.0: When should IAC activate? I can hear mine come on at start and then again after it idles down. As the idle comes down to ~800 rpms, it activates a couple times, then stops. But when driving the truck around, I can hear it activate when under slight load. Is this normal? Thx
Fleet Mechanic
Joined: Aug 2015
Posts: 1,832
Likes: 363
From: Candy Mountain
The computer will play with it all the time.
It's function and range is tested as a part of the KOER self diagnostic.
It is a good idea to run the KOEO and KOER tests once and a while to see if any thing gets flagged.
It's function and range is tested as a part of the KOER self diagnostic.
It is a good idea to run the KOEO and KOER tests once and a while to see if any thing gets flagged.
Cargo Master
Joined: Aug 2021
Posts: 2,253
Likes: 742
From: Maryland
Are you sure it's your idle air control you're hearing? I'm not sure I've ever heard mine, but I can hear my air pump air when it's in bypass mode. During key on engine running diagnostics, I can hear the EGR activate...
The IAC is potentially making adjustments any time your ECM thinks it's needed, especially when you move your foot off the accelerator pedal.
The IAC is potentially making adjustments any time your ECM thinks it's needed, especially when you move your foot off the accelerator pedal.
Thread Starter
|
Mountain Pass
Joined: Feb 2023
Posts: 131
Likes: 17
From: Binghamton NY
Yeah, pretty sure it's IAC. I've mucked around w/ it and hear a distinct air rush higher pitch sound when it opens. I have run KOEO and KOER tests and no codes. I just thought it would be similar to choke, it's on when engine cold and and then it should be off once engine is warmed up. But if IAC is used anytime when engine needs it; i guess it's ok. I just went through TPS re-setting and pretty sure i did it correctly, but wasn't sure if i mucked something up.
Cargo Master
Joined: Aug 2021
Posts: 2,253
Likes: 742
From: Maryland
Yeah, pretty sure it's IAC. I've mucked around w/ it and hear a distinct air rush higher pitch sound when it opens. I have run KOEO and KOER tests and no codes. I just thought it would be similar to choke, it's on when engine cold and and then it should be off once engine is warmed up. But if IAC is used anytime when engine needs it; i guess it's ok. I just went through TPS re-setting and pretty sure i did it correctly, but wasn't sure if i mucked something up.
When your Throttle Position Sensor tells the ECM that your throttle plates are closed, but the engine requires more air, the ECM opens the Idle Air Control valve and lets air in.
Thread
Thread Starter
Forum
Replies
Last Post
captain1997
1987 - 1996 F150 & Larger F-Series Trucks
2
Sep 1, 2011 09:38 AM
njf207
1987 - 1996 F150 & Larger F-Series Trucks
3
Jul 18, 2005 03:27 PM
