89 Eldorado engine misfire
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 8 of 8
HT4100 4.1, 4.5, 4.9 Discussion, 89 Eldorado engine misfire in Cadillac Engine Technical Discussion; Hi everyone, I have an 89 Eldorado that progressively started missing worse than it has in the past. Anyway, the ...
  1. #1
    CrustyCat is offline Cadillac Owners Member
    Automobile(s): 1989 Eldorado Biarritz
    Join Date
    Sep 2009
    Age
    48
    Posts
    13

    89 Eldorado engine misfire

    Hi everyone, I have an 89 Eldorado that progressively started missing worse than it has in the past. Anyway, the other day, going down the freeway, I could feel the car missing, at least that's what it felt like. Going up hills, the car would give a big "jerk" like it had just had a really bad miss while under load. The ignition module was replaced recently thinking that would fix the problem, but it hasn't. There are no codes set. I don't know how old the plug wires are, could they be the problem? Any suggestions would be appreciated. Thanks.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Dave S Texas's Avatar
    Dave S Texas is offline Cadillac Owners Enthusiast
    Automobile(s): '87 Coupe DeVille 4.1L FWD(New engine '08) 1981 F100 '03FXDL
    Join Date
    May 2008
    Location
    Austin(area), Tx
    Age
    70
    Posts
    855

    Re: 89 Eldorado engine misfire

    There are a few ways to check a misfiring plug. Cheap testers that attach between a spark plug and its wire will show if electricity is getting to the plug. Pulling each plug and reading it's condition is the tried/true way. Wires deteriorate over time, especially due to heat in the engine bay. If those plug wires are 10yrs/older, it would be a good/smart investment to replace them with a quality set. Replacing the plugs with the correct type is also a good idea.

  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
    74,755

    Re: 89 Eldorado engine misfire

    Don't forget the cap and rotor.

  5. #4
    CrustyCat is offline Cadillac Owners Member
    Automobile(s): 1989 Eldorado Biarritz
    Join Date
    Sep 2009
    Age
    48
    Posts
    13
    Thread Starter

    Re: 89 Eldorado engine misfire

    Well, I finally got my wires replaced. Almost got my arm stuck while replacing number 2.. During the process, I removed the throttle body/air filter unit and noticed that one of the connectors to an injector was crooked. The retaining clips were broke and one of the electrical connectors is broken off off the injector. So should I replace just one injector, or both? What other parts do I need, throttle body gasket set? Thanks for any input.

    Kevin

  6. #5
    drewsdeville is offline Cadillac Owners Master
    Automobile(s): 2011 Crown Vic LX, 2009 Chevy Malibu 2LT
    Join Date
    Oct 2004
    Location
    Oak Creek, WI
    Posts
    5,381

    Re: 89 Eldorado engine misfire

    Just the one injector will be fine.

  7. #6
    CrustyCat is offline Cadillac Owners Member
    Automobile(s): 1989 Eldorado Biarritz
    Join Date
    Sep 2009
    Age
    48
    Posts
    13
    Thread Starter

    Re: 89 Eldorado engine misfire

    Well, I ended up replacing both and it runs like a champ now. The only thing to do is replace the injector connector and I think I will be good to go.

  8. #7
    quins90lac's Avatar
    quins90lac is offline Cadillac Owners Enthusiast
    Automobile(s): 1990 Cadillac sedan devile
    Join Date
    May 2008
    Location
    Peoria IL USA
    Age
    32
    Posts
    616

    Re: 89 Eldorado engine misfire

    so you just needed a tune up ? Mine dose the same thing so right now im in the proses of doing a full tune up on her i hope that fixes it if not im thinking its the trans slipping. O how i dread changing out the trans its such a PITA . But in case i do have to change out the trans can the engien and the trans come out together or do the have to come out one at a time ? I've done it before but the last time i did it i took it out separate and i tiring to make it a little easier on myself.

  9. #8
    CrustyCat is offline Cadillac Owners Member
    Automobile(s): 1989 Eldorado Biarritz
    Join Date
    Sep 2009
    Age
    48
    Posts
    13
    Thread Starter

    Re: 89 Eldorado engine misfire

    Well, the thing that I've discovered on the housing that goes on top of the Throttle body unit is so tight to the connectors for the injectors, is if you aren't careful, you can actually break those connectors because that housing is kind of a pain to get on and off with all the hoses connected to it since some of those hoses aren't very flexible when it's cold. Anyway, after closer inspection, I could see that over the years, the corners of the injector connectors had been busted off from removing and installing the housing. I think one of the injectors was only firing intermittently because the connector and injector pin was getting ready to break, and then I broke off all the way. Now it runs pretty good and I think I'll just leave everything alone...

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