Hello everyone! I'm hoping you can help. About a week ago a warning light appeared on my dash, "restricted performance" and the car started jolting when I pushed on the gas or accelerated too quickly. My brother in law is a mechanic and said there were 3 codes, which I don't remember, that meant either air was getting into the gas tank, something was wrong with the air filter or something else. My question is, can this have been caused because I've been using regular gas instead of premium? The car was given to me and I didn't know it had to have premium until today. If it is caused by regular gas, should I wait until my tank is empty to fill it with premium or should I start filling it now? It's 3/4 full at the moment. And lastly, is this permanent damage or is it possible it could be fixed by using premium gas? Thank you so much for your help!
Amee

 

Please get the specific code numbers and post them here. The gurus on this forum will help you out, but they need to see the specific code numbers.

Also, do a search on this forum for threads pertaining to fuel octane, as there are some lively discussions about it.

And it is imperative that you indicate which engine is in your car, as the '03 S-Type has several engine variations. It's best to post the details about your car in your signature, so people helping you out will see which type of S-Type you have.

Finally, if you haven't already done so, please introduce yourself in the new members section of the Jaguar Forums. Thanks and good luck! Steve