Results 1 to 10 of 10

Thread: Jaguar Sovereign 4.0 (308)

  1. #1
    Junior Member
    Join Date
    Sep 2019
    Location
    Madeira Island
    Posts
    5
    Post Thanks / Like

    Jaguar Sovereign 4.0 (308)

    Hello everyone,

    I would be grateful if someone could help me.
    I have an automatic 1998 4.0 Sovereign and it has a problem in acceleration. When I press the throttle it faill at high rpm.
    My mechanic told me that it can be wear problems in the gear box.

    Regards.

    Paulo

  2. #2
    Junior Member
    Join Date
    Sep 2019
    Location
    Madeira Island
    Posts
    5
    Post Thanks / Like

    Smile Jaguar X308 4.0 - Problem

    Hello everyone,

    I would be grateful if someone could help me.
    I have an automatic 1998 4.0 Sovereign and it has a problem in acceleration. When I press the throttle it faill at high rpm.
    My mechanic told me that it can be wear problems in the gear box.

    Regards.

    Paulo

  3. #3
    Member Armond Jerome Peroni's Avatar
    Join Date
    Feb 2017
    Location
    Plymouth,Devon,U.K.
    Posts
    82
    Post Thanks / Like
    Hi Paulo and welcome to the Forum.
    First thing to do is plug a code reader in or get your mechanic to do it and see what codes you have(if any) and report back.
    Good luck.
    Armond
    Enjoy The Luxury Which Is The X308
    Jaguar XJ8 4.0 Sovereign LWB

    Colour:Emerald Green (HGG code)
    Year 2000
    120000 Miles and Rising
    J.E.C. Member

  4. #4
    Senior Member
    Join Date
    Apr 2008
    Location
    Further up the creek.
    Posts
    866
    Post Thanks / Like
    Hi Paulo,

    A generic code reader won't diagnose your gearbox problem if you have one.

    It may not be the gearbox though. You will have to explain your symptoms in a little more detail. "a problem in acceleration. When I press the throttle it faill at high rpm." could well be a faulty MAF meter. But your description is very vague, so give us some more details please!
    2000 Jaguar X308 4.0
    1973 Jensen Interceptor Mk III 7.2
    1969 Jensen Interceptor Mk I 6.3

  5. #5
    Junior Member
    Join Date
    Sep 2019
    Location
    Madeira Island
    Posts
    5
    Post Thanks / Like
    Hi,

    First of hall, thank you for your help.
    I agree with you "SV8Predator" I think is not from the gear box...
    When I identified the problem, I checked with a OBD II and appeared ignition erros and oxygen sensor. I don't know the erros code number because the mechanic didn't registed it. The mechanic cleaned it.
    However, I changed the MAF and the spark plugs but the problem remains. Now, I have no erros log in the OBD II.
    Last weekend I took a ride with him to mountain, from 0 to 1400 meters. Roughly halfway it starts to faill. I stopped it and I waited some time, maiby 15 minutes. After that it didn't fail anymore.
    I'm thinking it can be a problem with the crankshaft sensor or the oxygen sensor. What do you think?

    Regards,

    Paulo.

  6. #6
    Senior Member
    Join Date
    Apr 2008
    Location
    Further up the creek.
    Posts
    866
    Post Thanks / Like
    Sounds like classic ignition coil failure.
    2000 Jaguar X308 4.0
    1973 Jensen Interceptor Mk III 7.2
    1969 Jensen Interceptor Mk I 6.3

  7. #7
    Junior Member
    Join Date
    Sep 2019
    Location
    Madeira Island
    Posts
    5
    Post Thanks / Like
    Quote Originally Posted by SV8Predator View Post
    Sounds like classic ignition coil failure.
    In hall of them?

  8. #8
    Member Armond Jerome Peroni's Avatar
    Join Date
    Feb 2017
    Location
    Plymouth,Devon,U.K.
    Posts
    82
    Post Thanks / Like
    Do you have engine management light on or restricted performance.
    If you can put the code reader back on and see if any of the codes have come back and this time make a note of them
    Good luck.
    Armond
    Enjoy The Luxury Which Is The X308
    Jaguar XJ8 4.0 Sovereign LWB

    Colour:Emerald Green (HGG code)
    Year 2000
    120000 Miles and Rising
    J.E.C. Member

  9. #9
    Junior Member
    Join Date
    Sep 2019
    Location
    Madeira Island
    Posts
    5
    Post Thanks / Like

    Jaguar X308 4.0

    Hi,

    I changed the crankshaft sensor and until know it's ok. Anyway thank you for your help.
    Last weekend someone stole me the "Sovereign" back nameplate. Any of you know where can I by one?

    Regards,

    Paulo.

  10. #10
    Senior Member
    Join Date
    Apr 2008
    Location
    Further up the creek.
    Posts
    866
    Post Thanks / Like
    Quote Originally Posted by pnjervis View Post
    Any of you know where can I by one?
    Try Ebay. That's where I got mine.
    2000 Jaguar X308 4.0
    1973 Jensen Interceptor Mk III 7.2
    1969 Jensen Interceptor Mk I 6.3

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •