2002 1.4 16v petrol - missing vacuum hose?

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Bjorn9N
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Drives: 2002 1.4 16v petrol
Location: Oslo, Norway

2002 1.4 16v petrol - missing vacuum hose?

Post by Bjorn9N »

Pic shows engine cover vacuum hose connections on LHD car with the brake fluid reservoir on the left.

The car have been running for years with the (?) vacuum connection open when a mechanic discovered it was missing today. He was unable to find the other connection, so he temporarily attached a vacuum hose with zip ties to stop the leak. This resulted in much improved engine performance, but erratic idle.

Does anybody know where the "blanked out" vacuum hose from the engine cover should be connected?

Thanks,
Bjarne,
Oslo, Norway
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RUM4MO
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by RUM4MO »

My wife sold that car back in 2015, so I can't check that, but, from memory, the only pipe that needed removing when taking off the air cleaner assembly was the one that is shown still connected to the air cleaner just to the left of your red circle.

So your mechanic has doubled over that end of that pipe and fitted a cable tie to keep it closed off, where is the other end of that pipe connected to?

Edit:- or is that doubled over pipe the other end of the pipe that I was referring to?
Bjorn9N
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Drives: 2002 1.4 16v petrol
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by Bjorn9N »

Yes, its the vertical double over pipe coming from the same chamber after the air filter as the horizontal pipe on the left.

I have not found anything about it online. Maybe it was originally plugged?
RUM4MO
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by RUM4MO »

No, it would definitely have been connected to a part of the engine top area when it left the factory.

Have you not tried removing the air cleaner assembly and seeing where the end of that pipe want to sit or be as it is a preformed rubber pipe, maybe cut off that cable tie to let it take up its original shape, and pull the end off the air cleaner and then hold it by that end at the correct position above the engine, ie where it would be if the air cleaner was fitted to the car?

Edit:- when I worked on a car with that engine, I always pulled that pipe off the air cleaner before removing the air cleaner, no other way to be able to remove that air cleaner from that engine.

Another edit:- I think that if you do as I have suggested, you should find a black plastic air valve somewhere on the upper surface of the engine about half way along it, and that hose should be plugged into it, that air/vac valve should be on the engine at a position that it gets access to the crankcase and if nothing is fitted to that valve, it will be okay when the engine is running above idle probably, but when at idle it will could be letting too much air in, though when you think about it, if that valve is still fitted and working, it should restrict the air flow at idle (higher vac situation) and still work okay if that pipe is not connected as that pipe is only making sure that the air being drawn into the crankcase is free of grit etc.

Only one way to prove this and that is to get that air cleaner off and find that black probably oily air/vac valve - then fit that pipe back onto it.
Johntheo1
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by Johntheo1 »

I had a 2000 Bora for 19 years with that engine.
The Air filter body had only one crankcase hose connected directly from the filter housing to the crankcase breather. (No vacuum hoses anywhere)
It did have EGR with steel pipes from the exhaust manifold connected via the EGR valve to a nipple located just below the throttle butterfly, the EGR valve was actuated from a solenoid valve which was connected to a very small vacuum pipe to operate the EGR valve. Later engines (from 2001 onwards?) had the EGR valve electrically operated , the only other vacuum connection that I can recall is one for purging the charcoal filter.
RUM4MO
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by RUM4MO »

I think that the OP was referring to that pipe as a vac pipe, or maybe it was me, because air is drawn in through it as opposed to air being forced out of it.

The point on the engine crankcase that that pipe fits onto is drawing air into the crankcase.
Johntheo1
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by Johntheo1 »

If its the CC breather pipe that's tie wrapped and removed from the CC breather then I would expect to see a lot of oil around the CC breather and on the ground when parked up, I hope it hasn't been tie wrapped at the filter end while still attached to the CC breather as it will build up pressure in the crankcase and cause all kinds of problems as these engines are "heavy breathers".
RUM4MO
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Re: 2002 1.4 16v petrol - missing vacuum hose?

Post by RUM4MO »

The "U" shaped hose that you can see on the left side of the picture is that closed off hose's other end still plugged into the air cleaner.

It is really just down to finding the PCV and plugging that other end into it.
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