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D3 - Engine Bay Everything under the bonnet

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  #21  
Old 21st January 2019, 04:41 PM
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snapdragon snapdragon is offline
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How do Lee,
Thank you for your instructions.
I carried out these tests, but could not find a kg/h labelled block so used mg/s
The other thing was that in the idle test, blipping the throttle only changed the EGR duty cycle while the revs were dropping then all readings including duty cycle returned to what they were before the blip. I will try again now I have a better understading of the process though.

In the first excel document, I can where the EGR duty cycle changes over: (last column)
Code:
	375.21	777	5.2	475.7	86.4	374.87	777	1	 0 01   	86.4	375.04	777	246.8	493.5	20.9
	375.68	777	5.2	475.7	86.4	375.37	777	1	 0 01   	86.4	375.52	777	246.8	517	94.6
In the second file, I can see where EGR became disabled on row 120 which matches the freeze frame data of the error in the attached LOG file.

It seems as though the vacuum solenoid is very lazy. I cannot find a receipt for it, only the ebay sale of my old one (so I must have bought one). I can't remember if it was a chinese one or a used one or what, but I will take it off and see what the readings/manufacture is.

I put my vacuum pump either side of it with a T piece to use the pressure reading guage (not to pump). I found 850Hg/mm on the vacuum side and only ~150Hb/mm on the side that controls the EGR. While it does vary when doing the Basic Settings EGR ON/OFF test in Group 003, it is more of a half-hearted blip and return to 150. I will order a new Pierberg one.

I also think it has got worse, as when I used to do this test >1 year ago , there was a change in engine running/vibration between EGR ON/OFF, but only a tiny change in engine note.

Log-OV55YPU.txt

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Last edited by snapdragon; 22nd January 2019 at 05:05 PM.
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  #22  
Old 21st January 2019, 10:31 PM
Mechcanico Lee Mechcanico Lee is offline
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Hello I can not open some of them files on iPhone ...doesnít matter for now

Idle air mass is about correct with air mass calculator
Vacuum on feed side of egr vac solenoid seems good .
If you look at air mass on vcds at idle ,and pull the egr valve open with your vac gun what does air mass drop down to ?

Is egr valve holding the vac ok ....not leaking down a little past diaphragm .

Was boost actual following boost desired ok on the road .

On the road on light load 30 /40 mph or so what is egr duty cycle , if you put your foot right down does egr go to a low duty cycle reading ?

Yes ,get a proper egr vac solenoid



Are the engine mountings ,electric solenoids or vacuum controlled , Iím pretty sure they are electric but some cars have vacuum types .
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  #23  
Old 23rd January 2019, 12:12 AM
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snapdragon snapdragon is offline
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Thanks for the feedback Lee.
I have uploaded screenshots of the relevant parts of the log to my post above.
I will try opening the EGR with my gun when the weather is a bit better and my work shift is more sociable. I did do this and expected smoke or even stalling but not really any of either.
I did not use VCDS while I did it though.
Yes the EGR and all other parts that should - hold vacuum.
Yes boost actual vs specified is pretty good, see one of the screenshots.
Yes the EGR goes to a low duty cycle when accelerating and high on overrun 3-40mph but was disabled after just a minute of driving. MIL comes on some time later after I presume it has tried it again.

The mounts are all electric and the engine ones stopped working at <5 years old, the gearbox at ~6 years..
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  #24  
Old 10th February 2019, 06:25 AM
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Just a quick update and thanks for all the help. It was the EGR vacuum solenoid 059906628B. It is one of the first things I replaced in 2017 and was GEPCO branded from Germany for 60 Euroshekels.

I remember that after replacing it the EML light went off on it's own after a couple of days which was a first and a really good sign but came on a few weeks later so it was back to the drawing board and buying more parts. If I had the vacuum tools and troubleshooting knowledge back then I probably would have diagnosed the part as faulty and returned it.

As I assumed that it did not fix the issue, I sold the old one on ebay as working. So sorry whoever go that.

I now have a genuine used part for £20 with a 2014 date stamp.

The morals of the story ares that replacing parts needs to be done in-hand with proper diagnosis if possible.

Cheap Chinese parts are sometimes garbage (remember the aliexpress vacuum solenoid for the EGR cooler failed too)
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Last edited by snapdragon; 10th February 2019 at 06:28 AM.
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