850 T5 Turbo not working

Australian 850T5, delivered 1 Jan 1996 (does that make it a 95 or 96
model??). Turbo guage moves into the white area under wide open
throttle, but only slightly. Does not feel like there is any boost at
all. Feels like a normally aspirated 850 2.5. Runs relatively
smoothly. K&N air filter, nice and clean. I did find two vacuum hoses
with holes - one is on the intake manifold inboard of the power
steering pump. The other is at the bottom of the airbox intake hose,
down from the airbox below the rear engine mount. Both had big splits
in the rubber elbows. I will order replcements tomorrow, however, my
question is, would these two vacuum hose splits cause the turbo not to
operate. Car only has 65,000 miles. What is quite strange is that the
check engine light is not illuminated.

Any thoughts gratefully received.

Chris

 

Sounds like the actuator rod has come off the wastegate on the bottom of
the turbo. This will result in exactly what you describe, very little
boost, and no fault codes will be triggered.

 

Thnaks for the suggestion James.

I have replaced the perished vacuum hoses, and re-connected another
one that was not attached at the airbox. This has improved the engine
smoothness noticeably and the car seems to rev better to redline, but
still no turbo boost.

Could you give me any advice as to how to check the actuator rod? The
Haynes manual does not refer to it and has only 3 pics of the turbo,
none of which seem to show a rod.

Does it require the removal of what looks like a heat shield below the
brake master cylinder. The tubo looks to be beneath that. What am I
looking for, and is it common for the actuator rod to come of the
waste gate?

Thanks again for input

Chris

 

Thnaks for the suggestion James.

I have replaced the perished vacuum hoses, and re-connected another
one that was not attached at the airbox. This has improved the engine
smoothness noticeably and the car seems to rev better to redline, but
still no turbo boost.

Could you give me any advice as to how to check the actuator rod? The
Haynes manual does not refer to it and has only 3 pics of the turbo,
none of which seem to show a rod.

Does it require the removal of what looks like a heat shield below the
brake master cylinder. The tubo looks to be beneath that. What am I
looking for, and is it common for the actuator rod to come of the
waste gate?

Yes you will have to wrestle with the heatshield (and end up with skinned
knuckles) to get at it. Also replace the diaphragm in the recirc valve as
matter of course (they split) and that the hose is still connected to it (if
not it will open under boost and you'll get virtually no boost)

Tim..

 

I haven't looked closely at the turbo in an 850, but usually the
actuator rod is on the underside of the turbo and connects to a little
lever sticking out the bottom of the exhaust (cast iron) side. The other
end of the rod goes to the actuator which is a cylindrical thing with a
vacuum hose attached to it.