'88 DeVille EXTREME ISC problems
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 5 of 5
HT4100 4.1, 4.5, 4.9 Discussion, '88 DeVille EXTREME ISC problems in Cadillac Engine Technical Discussion; Hey everyone. I'm not sure if you all read my post in the FWD forum that my '89 Fleetwood was ...
  1. #1
    SlxAlxx's Avatar
    SlxAlxx is offline Cadillac Owners Fanatic
    Join Date
    Feb 2007
    Posts
    306

    '88 DeVille EXTREME ISC problems

    Hey everyone. I'm not sure if you all read my post in the FWD forum that my '89 Fleetwood was destroyed last weekend. I'm going to buy an '88 Sedan DeVille as it's replacement with only one issue: the E30 code. My Fleetwood had the code intermittently and would idle high when first started and went to normal about two seconds later every time. This DeVille idles in the correct RPM range, but the idle is VERY rough and sporadic. The engine is jerks but accelerates beautifully. The E30 code comes up every time the car is started, but not always right after starting. What I was wondering is if there was any issue besides the ISC motor (i.e. spark plugs, etc.). The current owner has claimed that a lot of parts have been replaced on it and according to my thorough inspection, they have been. Any advice to this novice would be greatly appreciated!

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    SlxAlxx's Avatar
    SlxAlxx is offline Cadillac Owners Fanatic
    Join Date
    Feb 2007
    Posts
    306

    Re: '88 DeVille EXTREME ISC problems

    I just heard from the current owner of the car that the ISC motor was replaced this year. Apparently, the technician that installed it did not adjust it. Is it true that I need a 12V power supply to be able to do such?

  4. #3
    awadecki is offline Cadillac Owners Enthusiast
    Automobile(s): 76 Eldo (54k), 76 Eldo (52k), 78 Eldo (9k), 85 Deville (43k)
    Join Date
    Jun 2005
    Location
    Michigan
    Posts
    668

    Re: '88 DeVille EXTREME ISC problems

    No, see my posts on the ISC issue (and also those by others). I personally think my adjustment method is easier.

    I also had an E30 code and traced it to a worn distributor drive gear. The slop in the gear was causing erratic idle timing, which the ISC was trying to overcome.

  5. #4
    SlxAlxx's Avatar
    SlxAlxx is offline Cadillac Owners Fanatic
    Join Date
    Feb 2007
    Posts
    306

    Re: '88 DeVille EXTREME ISC problems

    How did you repair that? (Just in case that may be my issue)

  6. #5
    awadecki is offline Cadillac Owners Enthusiast
    Automobile(s): 76 Eldo (54k), 76 Eldo (52k), 78 Eldo (9k), 85 Deville (43k)
    Join Date
    Jun 2005
    Location
    Michigan
    Posts
    668

    Re: '88 DeVille EXTREME ISC problems

    It's not too bad of a job. You have to pull the distributor (remove the hold down bolt and clamp), and pull straight up. Then, you remove the gear by punching out a small pin with a dull punch at the end of the distributor.

    When I removed the distributor, I took several pictures with my camera of the rotor position, then made sure that it lined up when I reinstalled it.

    If you have a timing light, jumped the 2 pins on the ALDL connector and check your timing. If the timing mark dances around a lot, this may be your problem.

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 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