Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Engine won't idle

Thread Tools
 
Search this Thread
 
Old Nov 15, 2005 | 04:24 PM
  #16  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by MICBAR
I went to autozone today, they couldn't read the codes at this time.
How come they could not read them at that time?
 
Reply
Old Nov 16, 2005 | 07:52 AM
  #17  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
They said it wasn't working.
 
Reply
Old Nov 16, 2005 | 11:36 AM
  #18  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
Engine Won't Idle

Subford....here's a photo. Is this the IAC or the TPS? Thanks again.
 
Reply
Old Nov 16, 2005 | 11:50 AM
  #19  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
It's an IAC.
Start the engine and while it is Idling pull the plug off, if the RPM's drop and then it dies, it is working. If nothing changes it is stuck or bad. If it is stuck, take it off and spray carb cleaner in and around the two holes. If you can put 12V on the two pins while it is off and watch for any movement inside, You will also hear a click.
When you take it off you remove the bolts that go into the throttle housing and not the screws that you can see in your photo.
 

Last edited by subford; Nov 16, 2005 at 11:57 AM.
Reply
Old Nov 16, 2005 | 11:58 AM
  #20  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
Yes I did remove the plug and the RPM's dropped and then it died. So this means it's working? I need to check the TPS?
 
Reply
Old Nov 16, 2005 | 12:38 PM
  #21  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by MICBAR
Yes I did remove the plug and the RPM's dropped and then it died. So this means it's working? I need to check the TPS?
Yes it is working OK (the IAC).

The TPS is more than likely OK but to check it, engine off, unplug it and it will have three terminals labeled A, B, & C.

You would need to +5VDC on C and the neg from the supply on A.

The center pin (B) is the output and will read (or needs to be) 1 VDC with the Throttle closed and about 4VDC open. The 1 VDC is the adjustment if it has one and needs be adjusted to one volt.

This is normally done with a breakout box hooked to the EEC and the one volt is at pin #47 (+) and #46 (-).

 
Reply
Old Nov 16, 2005 | 12:55 PM
  #22  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by MICBAR
My F150 recently started running rough, and now won't idle. The gas mileage is terrible! Someone said it was idle sensor, and to unhook battery to reset computer. That didn't help? The engine light stays on too. Will I have to have
someone hook computer up to it? Thanks.
OK, with all of that out of the way let’s rethink this. We need to read the codes and you say autozone will not do it for some reason. We need to ground a pin on the test (DLC) connector and watch the check engine light. Count the flashes and see what they say.

Here is how you do it.
http://fordfuelinjection.com/?p=13

Good luck
 
Reply
Old Nov 16, 2005 | 01:22 PM
  #23  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
Thanks subford....I will try this today after work. I really appreciate you taking the time to help me!!
 
Reply
Old Nov 16, 2005 | 02:05 PM
  #24  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
Ok...to check the TPS I will need to see if terminal C has +5VDC on it and the neg from the supply on A.The center pin (B) is the output and will read (or needs to be) 1 VDC with the Throttle closed and about 4VDC open? Correct? The 1 VDC is the adjustment if it has one and needs be adjusted to one volt.
Is this right?
 
Reply
Old Nov 16, 2005 | 06:08 PM
  #25  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by MICBAR
Ok...to check the TPS I will need to see if terminal C has +5VDC on it and the neg from the supply on A.The center pin (B) is the output and will read (or needs to be) 1 VDC with the Throttle closed and about 4VDC open? Correct? The 1 VDC is the adjustment if it has one and needs be adjusted to one volt.
Is this right?
Yes, but more closer to 5VDC on the open Throttle.

I do not know how you are going to do this without a breakout box or a portable 5VDC supply unless you stick a straight pin in the center B wire (GRY/WHT) and the other end of your meter to a good ground.

More than likely the TPS is non-adjustable and you will only be looking for the 1 VDC and 4.8 VDC readings with the key on engine off. If you get them it is OK.

 
Reply
Old Nov 16, 2005 | 06:57 PM
  #26  
cody123's Avatar
cody123
New User
Joined: Aug 2004
Posts: 16
Likes: 0
From: so cal
I am having the same problem with my 90' 351ci. the same symptoms as MICBAR's only the exhaust is really rich. I checked both the IAC and TPS the way subford explained and i found nothing is there anything else that could cause this Im pretty lost.
 
Reply
Old Nov 16, 2005 | 09:34 PM
  #27  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by cody123
I am having the same problem with my 90' 351ci. the same symptoms as MICBAR's only the exhaust is really rich. I checked both the IAC and TPS the way subford explained and i found nothing is there anything else that could cause this Im pretty lost.
cody123
I do not think and never thought that the IAC or TPS was his problem but I was just trying to prove to him that they were not his problem without him spending a lot of money.
More that likely he has a bad ECT, ACT, HEGO or MAP sensor.
I would like to see if he has any codes that would point to any of these sensors.
Of course the Thermostat could be stuck open too.
This would apply to your truck also.
 

Last edited by subford; Nov 16, 2005 at 10:29 PM.
Reply
Old Nov 17, 2005 | 12:58 AM
  #28  
cody123's Avatar
cody123
New User
Joined: Aug 2004
Posts: 16
Likes: 0
From: so cal
Does autozone rent out code readers because I dont wanna chance driving the truck with 2001 tags on it.
 
Reply
Old Nov 17, 2005 | 07:59 AM
  #29  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,666
Likes: 300
From: Easton,Ks
Originally Posted by cody123
Does autozone rent out code readers because I dont wanna chance driving the truck with 2001 tags on it.
You do not need one to get the codes, just go to this URL and it will tell you how.

http://fordfuelinjection.com/?p=13

And here is quick diagram borrowed from Dave Franklin's gallery.

 
Reply
Old Nov 18, 2005 | 10:30 AM
  #30  
MICBAR's Avatar
MICBAR
Thread Starter
|
New User
Joined: Nov 2005
Posts: 20
Likes: 0
OK last night I did the code test with the Engine Light. It ended up 63,63,11, & 11. I did this several times to make sure. Where do I find out what this means? Thanks.
 
Reply



All times are GMT -5. The time now is 05:25 AM.