Raise the car and remove the lower shields (8 mm hex screws). If you
have a 9-3, you might be able to access the radiator drain plug without
removing the shield.
Drain coolant, engine oil, and remove the oil filter.
Disconnect the downpipe from the turbo (three 13 mm nuts). If you have a
subframe brace, you might need to remove that too to allow more room to
move the downpipe aside.
Disconnect the return hose from the bypass valve if you have it (my car
has a BOV). Remove the rubber elbow between the airbox and the turbo inlet
Unbolt the turbo oil feed line from the filter housing (12 mm socket),
remove the oil return hose and undo the bolt that holds the turbo stay
to the engine.
Undo the banjo bolt on the lower coolant line (12 mm socket). On newer
cars the line goes to the water pump instead of the block. Put a catch pan
under the car as there will be coolant dripping.
Undo the banjo bolt on the upper coolant line (12 mm socket) on the left
side of the engine. Don't forget the pan again.
Disconnect all three lines from the turbo (more coolant drips) and remove
the lines if you can. On my car, I was unable to unbolt the upper coolant
Remove the intercooler hose from the compressor housing. Unhook the BPC
hoses. Unbolt the turbo inlet pipe. On T25+B204L, you might need to remove
the brass BPC hose nipple to gain the access to an inlet pipe bolt.
Remove the turbo inlet pipe together with the metal PCV line (there are
newer versions that allow you to unbolt the PCV line from the inlet pipe
instead). Undo the nuts connecting the turbo to the exhaust manifold
and pull the turbo down.
The turbo is removed from the car. You can see some of the lines still
attached to it.
New vs old
The turbo is being replaced with a
recently rebuilt unit.
Old vs new
Compare my old style inlet pipe to the new style (this one came from
a 1999 9-3), which allows an easy access to the PCV pipe bolt.
With my new upgraded inlet pipe, I can bolt it to the turbo prior to
installation and save myself some hassle. From this moment on, be extra
clean, as even a tiny grain of sand can ruin your new turbo.
Put the new turbo back in, and don't forget a new gasket for the exhaust
Install the oil return hose. Pour some oil into the turbo and install the
oil feed line.
Start connecting the lines to the turbo. Consider new copper washers for
all banjo bolts.
Connect coolant lines to the engine and tighten all six banjo bolts to
Tighten the nuts on the exhaust manifold (18.5 ft-lbs).
Connect the downpipe to the turbo, and re-install the subframe brace if
you had to remove it.
Fit the intercooler hose on the turbo, intake elbow and the BPC hoses.
Connect the bypass valve return hose, as well as the PCV line.
Refit the oil filter, fill engine oil and coolant. Before starting the car,
crank it with the ignition cassette harness unplugged to ensure there's
enough oil in the turbo.