Yes, go ahead and have it done, except for bringing it back to the shop.
Buy a can of injector cleaner and dump it in the gas tank. I went to
50,000 miles before I did it and although I didn't have any problems
before 50k, I didn't have any after either.

Knocking on wood, my 94 Maxima never had any issues with fuel injectors,
and I never used any cleaners.

Get a new mechanic because yours is either a hack (it's common for
hacks to suggest injector cleaning and tune-ups as cure alls) , or a
crook who wants to pay off his Motorvac machine.  Injectors made that
recently don't clog nearly as much as those from the 1980s or even
early 1990s, and gasoline has better additive packages than it used to,
thanks to EPA and auto maker requirements.  Injector flushing can
actually cause damage by dissolving insulation from the gasoline-cooled
solonoid coils, so it shouldn't be done unless the injectors are known
to be clogged and suspected to be in need of replacement anyway.  Just
use a bottle of Techron about every 10,000 - 15,000 miles.  It'll not
only keep injectors clean -- safely, but also remove carbon from intake
valves and combustion chambers.    It's also sold as Chevron Pro Guard
Clean Up, not to be confused with Stay Clean or Fuel Injector Cleaner,
which are more dilute.

I've just replaced the seals on my 150K mile '91 200SX turbo S13
CA18DET.  One 'O' ring had started leaking because one injector was
rotated to get access through nest of wiring to a hose clamp when a
water hose split.  Looking though the hole in the plastic cap, the
injector nozzles were bright and clean.  The plastic caps had a light
coating of carbon on them that cleaned up with one go round with a
paper towel soaked in jizer (gunk or paraffin will do).

It's had a few doses of "injector cleaner" over the last 6 years,
usually Wynns or STP.  But it's mainly down to the additives in modern
fuels.  The last 6 years it's been run on supermarket 95RON unleaded
petrol (92PON/AKI gasoline?).  It's had 2 fuel filter changes.

I've had problems with the fuel pump power supply due to an after
market alarm immobiliser circuit rated at 2amps on a fuel pump circuit
that draws 5amps.  In the process of finding this I had the pump out.
The tank was bright and shiny with no trace of sediment or
contamination, the only muck was in the filter sock on the pump which
was washed out and put back into service.
--
Peter Hill
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