Unless you drive primarily city with a lot of idle, start/stop and generally
short trips, your engines internals shouldn't have anything that needs
cleaning :-)

Basiccaly: if the engine needs internal cleaning, a brisk trip down the
highway cleans it out for you, OR there's something wrong with the enigne
management/carburator, ignition etc. that cannot be fixed with an additive

Don't waste your money, but you could use Shell V-Power [1] from time to
time...

[1] A Shell petrol with extra additives, that's supposed to clean the
intake, valves etc.
Other brands often have a similar type of petrol - all at a higher price
than normal petrol (that ALSO have cleaning additives....!)

I have used fuel cleaners as a standard about every 5000 miles on my older
cars (namely late '80s Saab turbos), combined with a good WOT blast. I run a
MK1 Punto as well and wouldn't bother on that one - just use a good fuel and
treat the car to a sporty run now and again.

I think tests in some car magazines showed they were a waste of money.

You are better off filling up with Shell Optimax every 4th tank or so, as
this does protect the engine and decrease wear. Evo magazine did a 6th month
test using it, and comparing Optimax against a car running normal unleaded,
the Optimax cars internals were a lot cleaner.

Dan TM.
Fiat Coupe 20VT.