1.4 16v aub engine pinking

[Johnr990]

Hi all,

Last week or so cleaned my egr pipe - blocked, reset codes, light back on with same code. Saturday took off egr valve and cleaned out and replaced. Light back on with same error code as below.

Monday, 04 August 2008, 13:03:49

VAG-COM Version: Release 409.1-US

Control Module Part Number: 036 906 034 BK

Component and/or Version: MARELLI 4LV 3700

Software Coding: 00071

Work Shop Code: WSC 17018

Additional Info: TMBHD46Y113225927 VWZ7Z0Y3280642

1 Fault Found:

16786 - EGR System: Excessive Flow

P0402 - 35-10 - - - Intermittent

Engine also pinking under load/acceleration.

My egr pipe has been blocked for about a year now engine not pinking, now unblocked pinking has returned (it used to do this from new when warmed up)

I have read many threads here about turning egr valve down using VAG com and also about adapting it. I am a newbie VAG com and would like to know how to turn it down and/or adapt it, as I cannot find facility in VAG com.

Can anyone help please?

[Johnr990]

Just an update on this;

Monday I tried to reduce egr flow by following the instructions provided by ross-tech wiki. Could not log in using 12233 as the access code, so I looked through the adaptation channels to find one that had the value of 32768 - chanel 15 had 32767 s I thoght bingo and proceeded to change it to 33768 as the instruction. There was no noticible difference at idle so I saved the change and drove home. On my way home I noticed the car pulling up sometimes on changeover from cruising to accelerating and a lack of power going up steep hills, however the engine warning light was out all the time and the pinking was massively less but not altogether gone!

Last night I checked chanel 15 again and found the value now 580! at idle and engine temp normal, so I bravely reset it back to 32767 and took car for test drive. Car now feels back to normal, more power going uphill but pinking like heck under load at normal running temp.

Does anybody know what chanel 15 is and is there another login code I could try to reduce egr flow?

Thanks:confused:

[Chris_55]

Found this info regarding exhaust gas recirculation valve adaptation, I think you will need to do this if you have replaced the EGR valve.

You may also need to clean the throttle body and the EGR inlet plate underneath it. Once done you will need to do a throttle body adaptation as well.

Display group 074 - Exhaust gas reduction, Exhaust gas recirculation valve adaptation:

Ignition on, engine stopped

Diagnostic device in function 04 “basic setting”

Field 4 = adaptation state (Ok or not OK)

Adaptation of the exhaust gas recirculation valve occurs with the ignition on.

The engine control unit is adapted to the exhaust gas recirculation valve by selecting display group 074 under function 04 “Basic position”. This adaption must always be performed if another EGR valve (or completely different engine) or another engine control unit has been installed.

[Johnr990]

Thanks Chris,

did that last night following Ross-Tech's wiki procedure as you say, plus I did a throttle body alignment as both had been disconnected. I only replaced original egr though after thorough cleaning.

It's interesting you say the adaptation of the egr should be done after a new ecu has been fitted as mine had a problem when new of cutting out after about half an hour's run and would not start very well. Dealers were scratching their heads, trying all sorts of things and finally said they would have to replace the ecu under warranty (£1000), which they did only to find out problem was a faulty fuel pump relay! To cut to the chase, my car pinked severely from then on until egr became blocked, hence my driving for last three years with engine light on!

Anyhow, I now have a car which runs smoother, accelerates cleanly with only a whiff of pinking on take-up of accelerating or climbing hills until knock sensor tells ecu it's had enough of that and ingnition timing gets retarded slightly, which I put down to car having to put up with ron95 supermarket petrol. Only slight niggles this morning are that after a few hundred yards there is a slight hesitation when cruising and also a little hunting on idle, both with engine warming up - fine when warmed through.

[Johnr990]

Final posting by me, I think I've stopped the pinking etc!

Lastly I performed the test function using VAG Com on measuring block 075. I struggled to hold an elevated revs for long enough for the test to run, so I took the car for a spin down the motorway with VAG com logging the reults of measuring block 075. When car was up to temperature and engine maintaining about 2300 rpm, test came on, ran and returned "system ok" now appears in last field where before it said "test off" and the 3rd field now has a value inserted instead of the zero.

Car now performs as it should, no pinking, no pulling up when cold and much smoother, quieter and acceleration clean as a whistle. in fact I've never had car running this well even when new!

[thinkpad]

Final posting by me, I think I've stopped the pinking etc!

Lastly I performed the test function using VAG Com on measuring block 075. I struggled to hold an elevated revs for long enough for the test to run, so I took the car for a spin down the motorway with VAG com logging the reults of measuring block 075. When car was up to temperature and engine maintaining about 2300 rpm, test came on, ran and returned "system ok" now appears in last field where before it said "test off" and the 3rd field now has a value inserted instead of the zero.

Car now performs as it should, no pinking, no pulling up when cold and much smoother, quieter and acceleration clean as a whistle. in fact I've never had car running this well even when new!

 

I know this is a very old thread, but does anyone know what block 075 is or what it tests?

Edited 31 October, 2014 by thinkpad