Thread: Sticking wastegate 300 TDI?

Yesterday on way home from long trip, largely at night, my 300 Tdi Defender lacked top end power and could largely not get to 100 kph on flat without head wind. Normally is readily capable of over 120 on speedo when passing on 110 kph roads. Has a boost gauge. It showed pressure never going over 10 psi when normally under load and with revs up enough it goes to the recommended standard 15 psi.


I stopped and tried to move the rod between the diaphragm and wastegate. Those familiar with 300 Tdi's know that this is under the manifold and difficult to access so need to think of some innovative way to apply much force to it. However, at this stage, seems to me that problem is likely to be wastegate stuck open. If so, does anyone else have suggestions on possible easy ways to free it up or other ideas on what the problem may be? I expect removing the manifold to check and fix the problem if my diagnosis is correct would be a "can of worms" type job involving dealing with bolts on manifold which are most likely seized.


Seems to me without having a close look at a standard 300 Tdi manifold removed from vehicle that a possibility would be to knock out the welch plug thing on the front of the manifold, which would almost certainly involve destroying it in the process. Before trying this, would like to know that this would be helpful to gain access for unseizing, have a replacement plug and be aware of any likely problems in process of installing it.


I recall reading comments on aulro from others complaining about lack of power from Tdi's for some obscure reason. Maybe the same problem that I have which those without a boost gauge would be given less clues about.

Check intercooler pipes, also the tube from the turbo to the fuel pump (name escapes me right now). Perished pipework is just as common as stuck wastegates.

Dont bother with pliers. Pull the wastegate air line off at the turbo, hook a compressor up to it and see if it moves (dont exceed 15 psi of course). If not pop the actuator arm off of the wastegate, the wastegate should move by hand.

I found it relatively easy to get at the wastegate from lying underneath.

Sent from my GT-S7562L using AULRO mobile app