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Thanks for the reply,
I'm learning as I go here just to make that clear. I understand what a turbo is and how it works but my practical experience with them to this point is limited to occassionally wringing the neck of my 855t.
As they say on the local news, "here's what we know...", I believe you're right about the hole in the actuator hose scenario. The actuator holds the gate closed and the result is excessive boost. Again, excercising my limited knowledge on the topic, manual boost controllers give you the "hole" in hose but a REGULATED hole.
When under the car I found the wastegate doesn't have any supplemental spring assist and is free to flap back and forth when the rod is disconnected. The actuator's diaphram places the rod in tension, clamping the gate closed. At the prescribed pressure, the actuator pushes the WG open.
Yesterday I found several pics of disassembled turbos on the web and I've learned what my WG actually looks like. Pretty simple but not what I expected. (Things rarely are, but that's for another forum.)
So I'm guessing here, with the rod disconnected, the WG was free to be pulled open by vacumn or neg exhaust pulses or some other exhaust event black magic and leak. I can tell you that during my 1100 mile drive back to Memphis, the boost guage behaved like it was tied to the gas pedal with a string. Step on the gas and the needle shot to 12:00 but never beyond. Very linear. Never went into the red (orange?). Once I connected the rod, I had no trouble pushing the needle into the red area. Disconnected, when revving the engine in neutral (to about 2k) the needle rose and fell with rpm. With the rod connected, the guage will rise then drop slightly while rpm remains constant.
Until I get under the car again and connect a pressure guage to find out just what is happening I can't offer any more information, fact or speculation.
I appreciate all the responses. I've been over on the 850 board for a year and learned quite a bit about those cars also. I hope along the way I've helped a few folk too.
BTW, how in the heck do I get my profile to stick? I keep adding my 740 to my sig but it won't update.
Regards,
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Erwin in Memphis, '95 855t
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