my friend own a 2001 S-type 3.0, he tell me the car problem, for the past month or he noticed when he pull up to a red light the car sputters, the car violently sputters unless when drive below 50 mph. can you please tell me whats going on.

 

Welcome to the forum camuar,

I've moved your question from General Tech Help to S-Type forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Could be a bad coil but more likely an air leak. Dozens of threads about both and how to diagnose & fix.

 

Thank you, all

 

Most likely a crankcase breather elbow finally failed.

 

Follow the link to Gus's site from the first paragraph in this link:
https://www.jaguarforums.com/forum/s...ics-faq-52720/