Engine sputters and smokes on large throttle openings and when revs over 2250

[Benbo]

Dear all,

A few months ago I knocked the rear-section of the exhaust off my 1994 3.0TD Surf. (166K km.) The section was heavily corroded and the remaining exhaust is probably no better.

The truck was running fine since, albeit a little throatier, until I accelerated hard up a slight incline. It kicked down ok but then sputtered a bit and smoked (dark/sooty). Ran fine for the remainder of the short journey home.

Now the engine starts to misfire/stutter at larger throttle openings and at revs above 2k or so. It smokes a lot when this happens (dark smoke). Effectively she's undriveable as I can't go up hills or accelerate.

I'm no mechanic but happy to tinker if I've got an idea what I need to do.

Any ideas where to start?

Thanks in advance.

[andyverran]

Turbo working ok?

[Benbo]

Turbo working ok?

Think so (light is green).

[tweak'e]

check you havn't kinked or partly blocked the exhaust. if its very rusty the muffler may be blocked up with rust.
is egr blocked off (plated)? if not egr could be stuck open. if someones done the dirty and just blocked the vac line to the egr valve, a big increase in exhaust back pressure could have forced it open and now its stuck open.