no turbo boost in 4th gear, any ideas?

[lee]

hi, my navara d22 has recently had a reconditioned engine and turbo fitted but shortly after it has started loosin power in 4th gear. i have had it at a couple of garages and they are clueless. it has turbo boost in every gear but 4th. i would but very grateful if anyone can give me any advice thanks

 

[Dave]

Neutral position switch on the side of the gearbox.

Dave.

 

[the_bluester]

This thread raises an interesting question to me. I am assuming that it is a D22 ZD30. Given that the D22 has no form of active boost control how does it manage that, or does it de-fuel the engine so hard that it does not make enough exhaust velocity to produce full boost?

 

[tweak'e]

yes exactly that. when the gearbox is in neutral it limits the amount of fuel and maybe timing as well. no fuel = no power.
typically neutral switch fails while in 3rd/4th gear hence the drop in power in those gears.