Thanks, I have sent him a PM and asked if he has a few minutes to look over the thread hopefully we can get this bypassed

 

I know how difficult this situation can be. I'm not sure my (resolved) issue bears any similarity with your situation, but you may wish to check out this thread:
https://www.6speedonline.com/forums/...-when-hot.html

My problem turned out to be caused by impedance in the wire coming out of the ECU. This was due to broken filaments within the wiring case. Unlike your issue, It would only manifest in extreme conditions.

 

my bet is primary fuel pump is bad. Secondary pump starts the engine and cuts off after 20 seconds or so. It will then only kick in under hard acceleration they both work. I had simular issues in a spur my other flying spur. I replaced both pumps with vw phateon w12 pumps.
less than $500 for both.

The reason your car runs when you jumped the circuit is that secondary pump did not lose power, however if you leave it bridged it will kill your battery as it will run constantly.

 

Indeed a possibility. Before pulling everything apart this can be tested at the relay. Pull the relay, on the primary positive and ground check if there is resistance. No resistance is an open circuit, bad pump.

 

Just got back from St Lucia and while I was there this exact thought hit me. Jumping the relays kept "both" pumps on aka the only working one. I had the guys replace the primary pump and the car seems to be running perfect.

 

Outstanding!!

 

that was a great troubleshooting session guys... i am super impressed...

what i thought when first read rhay jumping all fixed the problem i would just reconnect the relay banks - so the primary will start be a 2nd and 2nd pump will be the primary

no idea if technically possible to switch like that but would try so then will eliminate at least the fuel pump defects.

and here is the question - the both fuel pumps are identical /have the same params.

so in any emerg situation that one will fail the other will work we can switch them and ok... wont involve the broken 2nd in case of boost but you can operate the car right?

but smb said that on start engine the both pumps are engaged - the 2nd for 30sec.
is this correct? even if yes - it is no problem to start the care without 2nd pump operating?

 

did a scan today and have similar error

1. most important for me "18331 - please check drc memory of ecu number 2 - p1923 - 008 - intermittent"

you say - look for corrosion so should i disconnect bateries and then disconnect the plug from ecu located under the windshield plastic cover and finally apply some wd40?
this is what should be done?

and anyone can tell me how this connection look like to find the right one?


2. i also get in address 05:

"00181 - access/start authorization antenna (in rear bumper) (r136) 011 - open circuit"

something serious / what is this? what is its role where it is needed and how it looks like? should i check for broken connector here or smth?


3. finally i got the address 09: "01335 - drivers seat/mirror position control module (j543) - 004 - no signal / communication"

and correlated with that probably address 36: "01976 - seat depth adjustment motor (v234) - 005 - no or incorrect basic settings / adaptation

and correlated with that probably address 46: "01335 - driver seat/mirror position control module (j543) - 004 - no signal / communication

for this related to seat it looks like it is the reason i can not do memory set for driver seat - ive asked for help in other thread

i can not successfully do the callibration manually and with vcds i also can not do it - when being in " basic settings reset" the process starts and... the depth motor starts running but this part of the seat under the knee does not move so there is no way to understand by the computer it reaches the limits (thru resistance check i think) - so the procedure can not be completes - and no basic settings reset means no chance to make memory seat alive.

this is my theory - hope somebody will verify if i am right or not

thank you in advance for your help

 

P1923 is NOT A FAULT. It simply directs you to check codes on the second ECU. This, by far, is the most confusing P-code in the VAG series.

 

ok - so...

a) i shouldnt bother with the "corrosion" suggestions?

b) silly question - how to check on second ecu? i did only auto-scan so far and no other customizations

 

silly question first - the second ECU reports on vcds as address 11. When it has faults then address 01 reports a p1923. It directs you to look at the second ECU (address 11) for additional faults not listed or attributed to ECU 1.

On the first question check for corrosion as an incidental but it is not what p1923 means.

 

suspected it will be addr 11 - great name "engine ii" - but... there are no faults...

will do the stuff with ecu 2 corrosion check... but pls suggest me the procedure

should i disconnect batteries or this is not needed?
then disconnect the plug from ecu located under the windshield plastic cover
and finally apply some wd40 in plug and socket? wd40 is ok, or may lead to damages in electronics?

and anyone can tell me how this connection look like to find the right one / this?
do i need to remove some parts to get into the right plugs to check?

 

Does part# 3D0919087 work on the Bentley? This is the Pheaton fuel pump part I could find - the connector/wiring appears it's a little different. Can anyone confirm. Thank you!

 

If thats the pump for the w12 it will work, i dont have part numbers before me. but i did this on 2 different spurs.