How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Richard Your Own Question
Richard, Jaguar Technician
Category: Jaguar
Satisfied Customers: 15512
Experience:  12 years at a Ford/Lincoln Mercury and Jaguar dealer as technician and shop foreman.
Type Your Jaguar Question Here...
Richard is online now
A new question is answered every 9 seconds

Jaguar XJ8 L: My 1999 Xj8L warning light said enjine was in

This answer was rated:

My 1999 Xj8L warning light said enjine was in fail safe mode and didn't want to go over about 15mph. Any idea on what is wrong. Thanks
Hello and welcome to

Based on your description I suspect a problem with the electronic throttle system causing this. It is most likely a faulty in the throttle assembly which will need to be replaced. To be sure we will need the stored fault codes. A Jag factory tool is needed to read all the faults but you can try using a generic OBD II scan tool that can read the ECM only. I recommend a trip to your local parts store before visiting a dealer or Jag specialist shop. If no codes can be read then you need a Jag tool or the system needs to be scanned while the faults are displayed and it is most likely that throttle. You can try cleaning the throttle bore and blade to see if it helps. I suspect the code will be a P0121 and/or a P1121. Either way lets see if we can get a code number.
Richard and 3 other Jaguar Specialists are ready to help you