UK Car Repair: engine light?, exaust system, time hope

Question
HELLO,
JUST GOT 2 QUICK QUESTIONS,
FIRST, MY 97 ROVER HAS A CHECK ENGINE LIGHT ON, EVERY ONCE IN A WHILE IT WILL FLASH THEN STOP, MY EXAUST SYSTEM NEEDS TO BE SCREWED ON A LITTLE BETTER TOWARDS THE ENGINE, AND HAS A SMALL HOLE TOWARDS THE MUFFLER,  COULD THAT BE WHY IT IS ON AND BLINKING? OH YEAH I HAD THE LIGHT CHECKED BUT NO CODE POPPED UP.
LAST
MY RADIO AND AC SCREENS ARE FRIED, DONT WORK, BUT RADIO AND AC WORKS FINE, JUST GOT TO GUESS WHAT STATION AND HOW COLD OR HOT. FOR SOME REASON I CANT TURN OFF MY AC, ITS ALWAYS BLOWING. WHY?

OK, ONE MORE,
ON MY i BUTTON WHEN I PRESS IT, IT SAYS MY AVERAGE MPG IS 13.8, IS THAT NORMAL FOR A 4.0 RANGE ROVER?

THANKS FOR YOUR TIME, HOPE TO HERE BACK FROM YOU
DAVID

Answer
If the exhaust is leaking it could bring the engine light on, if no codes are recorded it's hard to diagnose but I'd get the exhaust sorted out and see if it helps. its all you can do really.

If the AC is permanently on it could be the computer has crashed, that could also cause the screens not to work - try disconnecting the battery for an hour or two and see if it sorts it.

14MPG is the posted economy for the vehicle, so 13.8 seems spot on - With that info given I would say the engine light is almost definitely because of the exhaust leak.