My son drove my car until it ran out of gas and and the check engine light came on and reduced performance light came on. We went to get gas and put in and then started it up and it sounds horrible and thick white smoke is coming from the exhaust. And the smell of gas is potent. What could be wrong?

 

First check all your fluid levels and check that none are mixed (oil and coolant specifically), then Try performing a hard reset by disconnecting the battery cables from the battery and holding them together for thirty seconds. Then reconnect and restart the car.

i would not be horribly surprised if running the car out of gas set some codes while it was Chugging on fumes. This would reset the modules is why I recommend it.

Try this and report back. If the codes persist and the running like crap persists, read the codes and report back.

 

Oh NOOOO!!!!!
What MAY have happened is dirt/grime/debris from the bottom of the fuel tank got picked up and MAY have fouled an injector!

Does the oil fill cap (crankcase) smell of gas/petrol (you didn't state your locale)???
If so, you may have a fouled injector. Sad face. If so ..... Do NOT drive it! All you will do is thin your oil with fuel and destroy your engine!
If not, still maybe, but maybe not.

 

Thank you so much guys! I’ll try it all.

 

Yes definitely a blocked injector , had the same on mine , get car recovered to a garage. Never let the tank run so low

 

Wouldn't it block the fuel filter first? Before it even gets to the injectors?

 

5.0 cars don't HAVE a 'fuel filter', just the sock around the pickup.

 

What DTCs are stored in the system?

+1 on sticking injector(s).

 

Many of us have had these same symptoms including me twice, and as Cee Jay and George05 have already said, it's a bad fuel injector.. it's going to cost you some to replace a bank of injectors, but it's not catastrophic, and your car will fully recover.

 

I agree probably block fuel injector, had the problem at 48K miles, luckily under warranty. The dealer didn't mention that the car doesn't have a proper fuel filter. OMG!!! why not?? anyone. Jaguar's way of selling injectors?

 

It sure sucks seeing how the xk version has a fuel filter that's not in the tank

 

. or don’t deal with it immediately and replace the cats before you know it, too.
There are many, many options for high flow, high pressure fuel filters. I must admit, this would be my priority modification, just like a catch can.

 

OP hasn't been back since "I'll try it" as a second post.