90 quattro injector prob/possible system contamination

[isham-research.freeserve.co.uk at pop.pol.net.uk]

> Folks,
> I wrote in earlier regarding power/hesitation problems with my '89 90
> quattro. I've taken it to a new mechanic who has diagnosed the problem as
> clogged fuel injectors.
> How common is fuel system contamination in the 90 series (1989) cars?

The system circulates fuel permanently, syphoning a bit off to run the
engine.  I seem to remember hearing that fuel could go round the system
five or six times before being burnt.  Each time it goes round, it goes
through the filter - which is a pretty massive and also pretty good
filter.

So there are two sources of contamination - something that passes through
a fine filter (water comes to mind) or something originating downstream
of the system pressure regulator.  Again, if it's corrosion related,
we're back to water.

First thing to try - if you always get your fuel from one source, change
it.  Second - try a commercial injector cleaner.

Two other points:

a) Never, ever fit second-hand parts unless you took them off a running
   car yourself.

b) Use Bosch specialists in preference to Audi dealers.  They simply
   see more cars.

--
 Phil Payne
 UK Audi quattro Owners Club
 Phone +44 7785 302803   Fax: +44 7785 309674