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Discussion Starter · #1 ·
Hi first post here wondering if anyone can help me?
I’ve recently bought this golf, got it for cheap as it had a few known issues that I was told about, just after fixing those issues, I’ve had my check engine light come on, reading the code is giving me p0402, which is excessive flow. However the car has recently had a new egr valve (fitted by previous owner, still looks new)

the only thing I can work out that could be causing it is there appears to be a missing vacuum line, the small connector on the side of the egr has nothing on it, but according to this diagram:
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It appears the missing link could be number 25, however I can’t see where a vacuum line would connect to. Anyone able to offer any insight? Am I looking for the wrong thing?

thanks
 

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Discussion Starter · #2 ·
Quick update: I realised there is 2 types of egr shown on the diagram. I believe mine is the 13A one, which has the vacuum line coming off labeled 39, going to 17, which is apparently a small air filter? Does that connect to anything in particular?
 

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Just a small line with the valve/filter thingy on it, doesn't connect anywhere else.

Excess flow is either bad a gasket, or an EGR sticking open. If it's new, it shouldn't be carbon making it stick, so it's either faulty internally or needs a new gasket.

Has the EGR been adapted?

Is the EGR aftermarket? They don't seem to work too well. Genuine used can be had for cheap.
 

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The 13A has a little breather on it which doesn't connect anywhere else. Bit like an oil catch can if you delete your PCV. Part 39 and 17 on the diagram.
I fitted a cheap EGR off eBay and it wouldn't adapt, but it doesn't throw a check engine or emissions workshop light. Solved the issue though (stumbling idle/stall when hot) so all good.
 
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