RE: pump is toast (was: intermittent stalling)

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <199810102314_MC2-5C49-8C64@compuserve.com> Craig Krivin writes:

> OK, now you’re getting ME nervous.  I acquired a 91 90Q about 2 weeks a> go. >
> I’ve noticed that upon a cold start, the red BRAKE light stays lit for > from
> several seconds to a minute or so, then goes out.  I’ve assumed that th> is
> was just a sign that it takes some time for “things” to pressurize.  > But
> I’ve also noted that the brake pedal is somewhat spongy.  The car has a> bout
> 69,000 miles.  Am I to assume that I to have to consider rebuilding my
> power steering pump?

IMO it's more likely to be the brake servo than the pump.

a) Pull the return line from the servo to the hydraulic oil reservior -
   carefully, because it's easy to break off the plastic return nozzle.
   It's sometimes a good idea to saw the clip off with a small hacksaw
   rather than extert torque on the reservoir.  If it drips continuously,
   however slowly, it's toast.

b) There should be a low pressure warning switch on the side of the
   turbo.  It should take 20+ brake depressions to cause this switch
   to close.  See how many it takes when the car is first stopped -
   less than around fifteen means a bad bomb.  Run the engine to
   charge the system up again (let it run for thirty seconds after
   the switch opens to indicate good pressure) and leave the car
   overnight.  Do another count in the morning - if it's only a few
   or none at all then the system has leaked down overnight (I suspect
   this is your problem) and the results of test a) above will tell
   you whether it's the servo leaking down or the bomb.

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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