Variable Vane control question...

Hoping someone has looked at this...does anyone know how much I should expect the linkage that controls the turbo to move when the vaccum diaphragm that operates this is being sucked on? If i operate the diaphragm by just sucking on it's vaccum tube it only moves about a quarter inch. I'm trying to track down why my turbo doesnt' create boost. Wondering if the linkage is crimped up or something. (I actually tried directly sucking on a hose connected to the diaphragm while driving with the engine under full load and didn't really notice any increase in power). Should I have noticed (even if there are also fuel delivery probs as well?).

Also, anyone know how those vaccuum solenoids are supposed to be setup? There are two hoses on one side (labelled vac and out) and one hose on the other. Which terminal goes where? (i assume "out" goes to the accessorie being actuated...little shaky on the other two).
Anyway...as always Thanks for any info in advance.
--Chris

[ November 17, 2002, 15:54: Message edited by: wwhalenc ]

Do you have VagCom data to support your assertion of no boost, or what makes you say you don't have boost?

Flaky MAF, clogged intake, clogged fuel/air filter/snow screen, all feel like no boost. With VagCom you log the boost(MAP) and MAF data for narrowing down the root cause.

A guy in my area was kind enough to hook up my car...the following stuff was wrong... MAF was reading ZERO. Fault code for the turbo solenoid was being thrown and the MAP reading wasn't changing at all. I'd love to send someone the data if they're interested. --cw

Send me mail. MAF putting out 0? Turbo Control Valve nonfunctional? And no MAP output? Interesting combination.

Well the Turbo Control valve not functionning and no MAP sortof go together. But having the MAF fail at the same time seems bizarre.

Does your car run???? I am an engineer statistician who love data.

If you were driving around with hoses disconnected from the N75 valve, the computer will detect that it has lost control of boost pressure, and throw a code.

If the MAF shows zero reading (I have seen this), the computer will limit fuel delivery to barely above what is allowed at idle, and without fuel delivery there is no energy left over in the exhaust to drive the turbo - and hence no boost pressure.

Replace MAF sensor with a new one, put all the vacuum hoses back to where they are supposed to be, clear all trouble codes, and report back with results ...

Under what circumstances would the MAF read zero? I actually threw on a 2.0 MAF...seemed to improve for the short term (and showed a little smoke), but now I'm not so sure. Perhaps it made a small difference that I'm already used to? Unfortunately I haven't been able to hook up to the lap top to see if this MAF is working (found out this weekend that VAGCOM doesn't work on Compaq Presarios!). From what I understand, even a "dead" MAF should be returning some reading.