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Discussion Starter · #1 ·

I posted a while back about a problem I was having with my PD130 Bora. To cut a long story short, it was going into limp mode fairly regularly.

Well, I cleared the fault codes using VAGCOM, so I could see what was causing it. Before it re-occurred, my laptop broke, so I was unable to check the faults.

It then seemed to right itself. I had no issues for a couple of months. I assumed that the turbo had been a little clogged, but hard driving had cleared it up. But the problem has reared it's ugly head again.

I have hooked up VAGCOM using a new laptop, and can see that the only fault which I can think could be affecting it is something like "N75 Open Circuit or Short to Ground". There is no overboost/underboost (as I would expect for a clogged turbo), and there are a couple of other ancillary faults (cooling fan was one, I don't have the list to hand). I am considering that the N75 may be faulty.

Anyone have any ideas?

Can anyone tell me where the N75 is located? I don't know my way around this engine.

I think I remember reading somewhere (I may be completely wrong, I have a memory like a sieve) that you can swap the EGR and N75 valves to check this problem, is this true?

Diesel isn't a dirty word
11,031 Posts
Have a look at the Sticky VNT link in my sig, there are vac hose and valve diagrams in there [y]

If your N75 isn't working then the VNT mechanism on the turbo won't be working and this will cause your limp mode [y]

From the fault you may have a dodgey connection or a broken wire if the valve checks out.

I was told the N18 and N75 were interchangeable but I can't be 100% sure that is the case though.

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