Hi All, I am new to site, I found it while looking for diagnostic procedures to help with my Audi. I have enjoyed the informative videos and incorporated the tests where I can.
I would greatly appreciate some guidance if anyone is willing to help.
My issue is with my Audi Q5 2.0 Tdi 2009. Bosch dual control injection system.
For about 3 weeks the engine has been rough idling no issues after 2000rpm. (No recent work done to cause fault and running fine for 18mths) I have Delphi DS150E software and a multimeter,
Findings so far; There are no error codes, the fuel pressure is very erratic, ranging from 16080kPa upwards (it changes so quickly that I can't read a top limit) the fuel consumption is 1.04 l/hr, inlet metering valve running at around 23% and fuel control valve at 22% both changing constantly.
I f I unplug the fuel pressure switch the motor runs smooth, (fuel pressure 200000kPa, consumption 0.44 l/hr), if I unlpug the imv nothing changes and with the fuel control valve unplugged the engine stops.
My multimeter tests results are as follows; pressure switch showing 4.95 v (red/grey wire) 0.5v (yellow/red) and a good earth (brown/green)(tested with test light) with ignition on engine not running, engine running 4.95v (red/grey) and 0.95 to 1.03v (yellow/red) and at 2000rpm the yellow/red is at 1.54v.
The pressure regulator (at back of rail) shows 13-13v (grey/white) and 11.70v (grey/brown) with engine running.
The imv shows 13.10v and 10.34v on each of the terminals.
The car runs fine over 2000rpm but is getting worse at idle particularly when cold (slight knocking this morning).
I have changed the fuel filter, very clean fuel came out of it, tried a used pressure switch and regulator valve and today fitted a new imv (no swarf visible in high pressure pump).
None of these changes had any effect. I think I have covered everything done/tested so far.
Any help with this "challenging" issue would be greatly appreciated. Thanks in anticipation Ant.
I would greatly appreciate some guidance if anyone is willing to help.
My issue is with my Audi Q5 2.0 Tdi 2009. Bosch dual control injection system.
For about 3 weeks the engine has been rough idling no issues after 2000rpm. (No recent work done to cause fault and running fine for 18mths) I have Delphi DS150E software and a multimeter,
Findings so far; There are no error codes, the fuel pressure is very erratic, ranging from 16080kPa upwards (it changes so quickly that I can't read a top limit) the fuel consumption is 1.04 l/hr, inlet metering valve running at around 23% and fuel control valve at 22% both changing constantly.
I f I unplug the fuel pressure switch the motor runs smooth, (fuel pressure 200000kPa, consumption 0.44 l/hr), if I unlpug the imv nothing changes and with the fuel control valve unplugged the engine stops.
My multimeter tests results are as follows; pressure switch showing 4.95 v (red/grey wire) 0.5v (yellow/red) and a good earth (brown/green)(tested with test light) with ignition on engine not running, engine running 4.95v (red/grey) and 0.95 to 1.03v (yellow/red) and at 2000rpm the yellow/red is at 1.54v.
The pressure regulator (at back of rail) shows 13-13v (grey/white) and 11.70v (grey/brown) with engine running.
The imv shows 13.10v and 10.34v on each of the terminals.
The car runs fine over 2000rpm but is getting worse at idle particularly when cold (slight knocking this morning).
I have changed the fuel filter, very clean fuel came out of it, tried a used pressure switch and regulator valve and today fitted a new imv (no swarf visible in high pressure pump).
None of these changes had any effect. I think I have covered everything done/tested so far.
Any help with this "challenging" issue would be greatly appreciated. Thanks in anticipation Ant.
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