TD4 - Engine light on - SOLVED (FINALLY)

Good day all,
I am experiencing an issue with my TD4 2.0D, I suspect a turbo related problem.
The engine light recently came on, shortly before it did I heard a strange hissing sound from the turbo area when applying the gas. Power seems to be okay except when going uphill, where the engine starts to labour a bit and a lot of black smoke coming out the back of the exhaust.
The engine light tends to go off when going downhill, so its very intermittent. Any ideas where I should be looking?
Many thanks

First check is all the intercooler hoses for splits or loose clips. The splits hide so get your hand around all of them including at the turbo.

I agree very likely the pipe from the turbo to the ontercooler

intercooler

LRNoob42 said:

Any ideas where I should be looking?

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As said, boost hoses.

great, thanks will check the hoses. recently replaced the top hoses with silicon units but not those of the turbo down the back of the engine.

Hello all, im back and still have the same issue. Have checked all the hoses and dont seem to find any leaks, I had a mechanic friend take a look and he cannot find any issues either. We put the LAUNCH diag on the car and it picked up the error code Error code P0046 - Variable Nozzle Turbo Neg Deviation. Car drives okay but when going up hill still cutting out at 2500rpm. Any other thoughts on what i can try. I did change my EGR valve and put a blanking kit in, but its also making a strange buzzing sound when running so i am going to change back to the original EGR.

LRNoob42 said:

and it picked up the error code Error code P0046 - Variable Nozzle Turbo Neg Deviation.

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maybe related to the turbo vane mechanism ?
sticking vanes
leaking diaphram .. or weak spring .. on the actuator
turbo vacuum solenoid sticking
leaking vacuum hose [ would it hiss / cause a buzz ? ] .. or the blimp reservoir ..
map sensor ?
( edit to add ) .. turbo vac. filter
i.e. if it's clogged up .. turbo vanes won't move as they should
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very pleased to say that i found the issue. it was the MAP sensor on the manifold which fell out and dangling just out of sight. somehow the bolt came loose. Thanks for all your help.

That would affect the boost pressure!!

Please edit title of thread to show 'solved' to help others. Thanks

now the next challenge is to get a bolt back in without taking half the engine apart.

Easy enough to lift the inlet manifold off, then you can clean it too!!

silly question but does anyone know the size bolt i need in order to fix the MAP sensor back onto the manifold? I tried google but cannot find anything except that it might be around 10mm in length. thanks

From memory, it's an M6 x 12mm standard flange head, which takes a 8mm spanner. There are loads around the engine bay of a FL1.

Nodge68 said:

From memory, it's an M6 x 12mm standard flange head, which takes a 8mm spanner. There are loads around the engine bay of a FL1.

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fantastic, thanks very much