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

Reply to
Chris
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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.

Reply to
James Sweet

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..

Reply to
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.

Reply to
James Sweet

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