High idle after TB cleaning - 96 Eldorado (solved)
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 4 of 4
Like Tree1Likes
  • 1 Post By Submariner409
Cadillac Tech Tips - How to fix it Discussion, High idle after TB cleaning - 96 Eldorado (solved) in Item Specific Cadillac Discussion; just to throw this out there: cleaned the throttlebody and iac yesterday, didn't take out the tb for that, only ...
  1. #1
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106

    High idle after TB cleaning - 96 Eldorado (solved)

    just to throw this out there:

    cleaned the throttlebody and iac yesterday, didn't take out the tb for that, only unscrewed the maf (cleaned it as well) and the iac and cleaned it as good as possible with a rag and carb cleaner. so, after putting everything back together she started to idle at like 1200 rpm and showed pc0507 (idle too high), together with a "service idle control" message. before the cleaning everything was working fine, so i figured it must have something to do with what i took off. so i played around a bit with the iac valve, pulling, pushing, turning and so on. checked for something that might block the throttle, like a piece of rag or carbon residue left over. found nothing like that. took her for a spin, thinking some adjustments might be necessary and over time driving around idle may get normal. well, didn't happen and i called it a day.

    today i took everything apart again and inspected again and looked around here to see if i can find something out. not really... so i figured that the iac actually is working, since i can feel the movement and it most likely closes completely, that not being enough to restrict air flow. or a vacuum leak... so i went on and sprayed (starter spray) around, no obvious leaks.

    then i thought maybe the throttle stop screw (red circle in the pic, 15tx) has been fooled around with sometime and probably the clean tb lets more air go through than usual and that's causing the high idle. and sure enough, after like 2 turns out and making sure that the throttle still is stopped by the screw, rather than the tb itself the idle went down to what it's supposed to be and the iac is regulating now.

    i'm just writing this up for somebody that has excluded everything else on their search for high idle after tb cleaning and can't be sure that this little screw hasn't been fooled around with. generally it has to be left alone the way it left the factory, but if some shade tree mechanic at an earlier point thought it's the idle set screw, then you might as well have to look into that, if everything else is working ok (no vacuum leaks, tps ok, iac ok, etc.)


  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Submariner409's Avatar
    Submariner409 is offline If it won't run, stick on fender vents
    Automobile(s): 2002.5 F55 STS/65500mi, 2004 Ford F150 SuperCab4x4
    Join Date
    Feb 2006
    Location
    MD Eastern Shore - Kent Island
    Age
    74
    Posts
    44,575

    Re: High idle after TB cleaning - 96 Eldorado (solved)

    Nice writeup. I'll move this to Cadillac Tech Tips for everyone to use. Thanks.
    el_dorado_mex likes this.

  4. #3
    Ranger's Avatar
    Ranger is offline Cadillac Owners Member
    Automobile(s): White Diamond '03 DHS (with DTS floor shift)
    Join Date
    Jun 2004
    Location
    Woodstock Ill.
    Age
    66
    Posts
    73,345

    Re: High idle after TB cleaning - 96 Eldorado (solved)

    Well I'll be dipped. Never would have thought about that. Nice catch.

  5. #4
    el_dorado_mex's Avatar
    el_dorado_mex is offline Cadillac Owners Fanatic
    Automobile(s): 1996 El Dorado and 1991 Cheyenne Pickup
    Join Date
    Jul 2012
    Location
    Puerto Escondido, Mexico
    Age
    36
    Posts
    106

    Re: High idle after TB cleaning - 96 Eldorado (solved)

    thanks guys. i was surprised how much of a difference in airflow this tiny throttle movement can make...

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may not post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting