A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D3 > D3 - Engine Bay

D3 - Engine Bay Everything under the bonnet

 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #21  
Old 21st January 2019, 05:41 PM
snapdragon snapdragon is offline
Senior Member
 
Join Date: Nov 2011
Posts: 1,669
Default

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.

Attachment 20748

Attachment 20749

Attachment 20750

Attachment 20751

Attachment 20752

Attachment 20763

Attachment 20764

Last edited by snapdragon; 23rd April 2020 at 09:18 AM.
Reply With Quote
 

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 08:09 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.