Here's how I think the fault code P0235 came about.
1. The 2" rubber hose connected to the turbo compressor side, had oily
gunk inside. Over time, this oily stuff was drawn into the compressor under high rpm.
It worked it way past the compressor wheel and eventually blocked the little pipe
supplying the boost pressure solenoid thus, stopping movement of the wastegate
via the solenoid. Wastegate would never open, resulting in,
2. Boost pressure was increased (the wastegate couldn't open, because the solenoid
wasn't getting the required air supply) The MAP sensor see this increase straight
away, in the inlet manifold reported this to the ECU, which said................NO
WAY!!! Resulting in LIMP MODE response. Up goes the fault code P0235.
3. As for the non movement of the turbo impellars, I suspect, could be wrong on
this, but the same oily gunk which blocked the little pipe which eventually operates the
solenoid, was the same contamanent which stopped the compressor wheel dead in its
tracks. After all, they spin very easily I notice, and I also suspect it wouldn't take
much to stop them either.
John.
1. The 2" rubber hose connected to the turbo compressor side, had oily
gunk inside. Over time, this oily stuff was drawn into the compressor under high rpm.
It worked it way past the compressor wheel and eventually blocked the little pipe
supplying the boost pressure solenoid thus, stopping movement of the wastegate
via the solenoid. Wastegate would never open, resulting in,
2. Boost pressure was increased (the wastegate couldn't open, because the solenoid
wasn't getting the required air supply) The MAP sensor see this increase straight
away, in the inlet manifold reported this to the ECU, which said................NO
WAY!!! Resulting in LIMP MODE response. Up goes the fault code P0235.
3. As for the non movement of the turbo impellars, I suspect, could be wrong on
this, but the same oily gunk which blocked the little pipe which eventually operates the
solenoid, was the same contamanent which stopped the compressor wheel dead in its
tracks. After all, they spin very easily I notice, and I also suspect it wouldn't take
much to stop them either.
John.
Last edited:
