Freelander 1 Boost solenoid / VNT linkage

So I think Ive fixed the lack of power / poor MPG issues Ive noticed on my TD4, by swapping out the boost solenoid, cutting some fresh ends on any perished vac pipes, and cleaned up the contacts on on the MAP sensor plug. A quick test drive and the car definitely seems to have a lot more low to mid end grunt with a noticeable difference in engine tone - though Ive not had it on the motorway yet to check the top end power.

Just wanted to check something with the turbo gurus: I can see the VNT linkage operating, by peering through the access in the drivers wheelarch while giving it a bit of throttle. Question is, how much movement should I see from a healthy VNT/Actuator? If I hold the throttle to about 2k revs, the linkage slowly raises about 10mm, takes a couple of seconds to lift and return. Is this normal? Or should I be seeing more rapid movement over a greater distance?

Thanks in advance

Sounds about right. Have you checked all the vac hoses for rubbing, causing leaks?
The actuator moves about 15mm in total. However it won't move more than needed to get the correct boost for the power needed at the time. You'll need to look at the actuator while under full power conditions. You'll need to record it with a sport type camera and review the footage later.

Nodge68 said:

Sounds about right. Have you checked all the vac hoses for rubbing, causing leaks?

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Checked as far as I can see - 1 to actuator is good but old, will be replacing. Next one goes to the vac chamber via a little inline filter at the back of the engine bay, filter looked clean - the remaining pipe I could follow very far before losing it - but thats marked "ATM" (atmosphere?) and seems to be an outlet to nothing, so Im not concerned with that one at the mo. Intercooler pipework appears to be good too.

The EGR has been blanet off with a dummy valve, though I couldn't see where the original vac pipe has gone to. Ran out of daylight, will find that another time

Thanks for conforming travel of actuator linkage, gave the unit a good douse in WD40 as its clearly not seen any movement in quite some time - hoping a test drive on the motorway tells me everything I need to know from here!!