It's like it can't shift into the next gear. 35mph is the fastest it will go. What in the world is wrong with this car?

 

If you've no messages use OBD:
1. do not clear codes
2. any pending codes other than P1111 or P1000? (You want P1111)
3. check OBD monitors - are all set (will be confirmed by pending code P1111)
if any are not, which?
4. watch live data in the hope you see an oddity
(might be a wrong temp or air leak or ...)

In case you have P1000 then each unset monitor means a ton of codes which can't be flagged.

 

Had a similar issue with my XF . After a lot of troubleshooting, found that one of the impeller blades of turbo had broken and got stuck in causing it to not function. Turbo had to be replaced.

 

He is in Alabama? The US never got any diesels and no turbos?

JagV8 gave him excellent advice but he has not replied?
He did not tell us what engine or any other details and with 1 post I doubt we will ever hear from him again?
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