EGR valve breather hose ok?

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

EGR valve breather hose ok?

Post by Bjorn9N »

I have just changed the EGR valve on a 2002 1.4 16 petrol. I re-attached the breather hose, but wondered the plastic end piece(valve?) is OK or if a cover is missing?

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

Re: EGR valve breather hose ok?

Post by Bjorn9N »

Found a part catalogue drawing (https://ifinterface.com/ under Free Services, CarProg2) which denotes the end part as Air Filter. From the drawing it does not seem to have a cap, so this is probably OK :D
RUM4MO
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Re: EGR valve breather hose ok?

Post by RUM4MO »

Yes, that is okay. I use that parts site a lot!

Edit:- did you check that the pipe that goes into the Throttle Body is clear, it usually gets chocked at that end leading to reduced flow.

Also you should perform basic settings to let the engine ECU know the voltages for the EGR plunger end stop positions.
Bjorn9N
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Re: EGR valve breather hose ok?

Post by Bjorn9N »

I have changed the EGR, performed basic settings and tested the EGR.

Have also looked at the EGR-throttle body pipe, but as it was not fully blocked I thought it would provide sufficient flow and did not clean it.
Do you think reduced flow in the EGR-throttle body pipe could cause erratic idle?
RUM4MO
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Re: EGR valve breather hose ok?

Post by RUM4MO »

I don't know, but the EGR pipe itself was clear and did not need sorting out, it was the hole in either the Throttle Body assembly, or in the case of my wife's 2002 Polo 1.4 16V, the interface plate below the Throttle Body where that EGR gas pipe is connected to, was very choked up with what looked like black grease - that would be the effect of very hot exhaust gases meeting up with engine oil mist being dragged into the inlet manifold by the induction depression or slight vacuum.

I bought and replaced the EGR valve just because I had bought a genuine NOS one from ebay, I don't think that there was anything wrong with the original EGR valve. I was just chasing down what was becoming quite severe pinking/pinging under load, even in winter time!
That eventually turned out to be due to the oil separator not working very well and so allowing too much engine oil to be drawn into the inlet manifold with fresh oil, the overall effect that can have is to reduce the effective octane rating of the fuel as the B1 S1 (controlling) Lambda sensor would reduce the mixture or injector firing period as it was sensing that too much fuel was being supplied - as the engine was using this unwanted engine oil as fuel, so the timing would be getting retarded as much as possible and still under low speed engine loading this was not stopping pinking/pinging. My quick fix until I finally sorted things out by replacing that oil separator was to only up 98/99 octane rated fuel - that worked very well! Plus using that fuel on that 1.4 16V 75PS engine improved low engine speed torque - my wife loved it so much that after I sorted that car out, I was not allowed to refuel using 94/95 octane fuel! That sorted out that car's need/liking for engine oil top ups!

For unstable idle I'd be looking at all the brake servo vac piping as it can end up cracking where you can't see it!
Bjorn9N
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Re: EGR valve breather hose ok?

Post by Bjorn9N »

Thanks for sharing!

I have checked quite thoroughly without finding any vacuum leaks in the brake servo piping or elsewhere.

I get error code: P0106 - MAP sensor range/performance problem, where one of the described fault sources include carbon buildup in the EGR valve vac line.

I plan to measure the MAP sensor and clean the EGR valve vac line tomorrow!
Johntheo1
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Re: EGR valve breather hose ok?

Post by Johntheo1 »

Due to the position of the EGR inlet to just below the throttle plate the very hot gases carbonized the oil and the throttle plate would stick when "closed" the revs would drop and the ECU would then advance the timing to compensate with resultant heavy pinking when accelerating again, this started to happen on my 2000 (cable throttle) Bora at around 80000 miles but I copped on pretty fast and just squirted some WD40 (didn't have any carbon cleaner) on to the throttle plate and let it soak for awhile, I then jammed the accel pedal down to keep the throttle plate opened and carefully cleaned off the carbon with a rag wrapped around a screwdriver, some remove the whole throttle body to do this.

I also got this MAP sensor fault up as well when the above started happening but it disappeared after cleaning the throttle body.
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