vnt turbo actuator rod

[olds_kool]

removed and stripped my turbo today to investigate a lack of power problem (99 a4 afb 2.5 tdi, garrett vnt20)

ive given it a good good clean and vnt internals work perfectly now
but my question is how far should i be able to move vacuum actuator rod? ive attached a hose and sucked as hard as possible and it moves rod about 1cm, and pushing rod by hand takes a hell of alot of force to move past the 1cm, is this right?

[Alan02]

Hi, i dont have any info on the dimensions you ask,but,to get the cell to operate the rod you would use a Vacuum gun to test it.You cant generally get it to move far by your method.Also,it is under a very strong spring pressure.The length of the actuator rod is factory set and should be left at that length.Have you checked all the hoses for splits? Remove to check properly.Any fault codes?

[olds_kool]

cheers alan
removed and cleaned it as it was coming up with 00575 intake manifold pressure fault code,
refitted yesterday and vnt actuator works perfectly, and car was much better to drive but still seemed to lack power, so i tried driving it with maf disconnected and it drove perfectly, pulls perfectly right up to 4000rpm which it hasnt done in ages
so is this 100% conclusive proof that maf is knackered or is there anything else i should check before giving audi parts dept a ring?