[s-cars] 94 S4 hesitated

[Dave Forgie]

Sam:  Sounds like your New Zealand car has the digital boost gauge our
North American cars only got on the 92 spec cars. The gauge is absolute,
i.e 1 Bar basically = one atmosphere = no boost.  So you have lost
boost.  There are two hoses that you need to know about:

1. Underneath the black plastic cover on the fire wall (held on by two
plastic Dzus fasteners (turn them 90 deg only), is a little boost line
going into what looks like a black film can.  The OEM clamp gets week an
it lets the hose come off the nipple on the can (moisture trap).
Replace the clamp with a small gear clamp.

2. The "Michelin Man" hose between the crossover pipe and the
intercooler inlet (you need to take off the belly pan to find this
one).  Oil accumulates in the ridges of the hose and rots the rubber
from the inside.  You can't necessarily see the crack in the hose but it
probably is there.  Check and replace this hose.  Many people switch to
a silicon rubber hose from Samco.

Good luck.  Kiss a sheep for me. ;>)

Dave F.






Hi
94 S4 6 speed
I was driving hard(ish) up a hill the other day when suddenly a massive
hesitation occurred, like someone had turned the key off, then on, then
off, then on. This has repeated itself since from about 1.2 bar up on
the digital boost/vac readout. Mid throttle driving is fine. All other
gauges etc read OK.
I drove it again today, initially it did the same thing, then the boost
readout went flat at 1.0 bar and the hesitation appears gone. The boost
reads 1.0 bar no matter what speed/throttle position, whether full boot
up hill or full overrun downhill or at idle. Power seems normal,
everything drives smoothly.
All other readouts are as normal (fuel economy etc readouts)
What gives gurus?
Sam Clarkson