Long cranking to start engine after sitting. ?? Fuel pump prime function

wotseurba · Mar 20, 2019

Looking for assistance on this. Owner complained of "hard starting" which I determined was really longer than typical cranking time to start of 3 - 5 seconds. This vehicle typically started up almost instantly upon cranking. It needed a lot of service, oil leaks, and carbon removal of intake valves and runners, as well as spark plugs, and a general full service change of fluids, etc. No codes present before beginning work pertinent to engine. Completed the service which did not solve the long crank issue. Fuel pressures while running are within spec., HP fuel pressure raises as expected upon shut down on hot, but LP fuel pressure leaks down to 2 bars within 15 minutes of shutdown. I assume this car has a LP fuel pump prime function when opening the drivers door, or turning the key to ON. LP tank pump does NOT run in either of these cases. I back probed the fuel pump connector to look for voltage for prime function and see none. Voltage appears after cranking begins, and after engine starts. Fuel pump test indicates the pump runs well, and on-road performance is good, so I don't feel the electric pump is faulty, but I could be wrong. I feel the electric pump SHOULD be priming before starting, but I don't know where to begin troubleshooting.

I add the full auto scan below from today below as well as an engine scan from earlier that showed two codes which may offer clues. These codes disappeared without being cleared by me.

Any tips, assistance, or comments are welcome.

Code:

VIN: WAUDH98E06A142220   License Plate: 


Chassis Type: 8E (8E - Audi A4/S4/RS4 B6/B7 (2001 > 2008))
Scan: 01 02 03 08 09 0F 11 15 16 17 18 25 36 37 45 46 55 56 57 65
          67 69 75 76 77
 
VIN: WAUDH98E06A142220   Mileage: 235930km-146600miles
-------------------------------------------------------------------------------
Address 01: Engine (AUK)       Labels:. 06E-910-559-BKH.clb
   Part No SW: 8E0 910 559     HW: 8E0 907 559 A
   Component: 3.2l V6 FSI         0050  
   Revision: --H16---    Serial number:               
   Coding: 01040109190F0120
   Shop #: WSC 06335 000 00000
   VCID: 6ADB065F45B7241A63-803E

No fault code found.
Readiness: 0110 0101

-------------------------------------------------------------------------------
Address 02: Auto Trans        Labels: 09L-927-760.lbl
   Part No SW: 8E1 910 156 E    HW: 09L 927 156 B
   Component: AG6 09L 3,2 FSI USA 0040  
   Revision: --H01---    Serial number:        4105809
   Coding: 0000002
   Shop #: WSC 06335 000 00000
   VCID: 295939538031EF02AA-807C

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes        Labels: 8E0-910-517.clb
   Part No SW: 8E0 910 517 E    HW: 8E0 614 517 AL
   Component: ESP8 quattro    H05 0120  
   Revision: 00000000    Serial number: 00000000000000
   Coding: 0004532
   Shop #: WSC 06335 000 00000
   VCID: 295939538031EF02AA-807C

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC        Labels: 8E0-820-043.lbl
   Part No: 8E0 820 043 BM
   Component:   A4 Klimaautomat   2832  
   Coding: 00000
   Shop #: WSC 00000  
   VCID: 6DD10D432759332206-5122

No fault code found.

-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels: 8E0-907-279-8EC.lbl
   Part No: 8E0 907 279 L
   Component: int. Lastmodul  USA 0504  
   Coding: 01023
   Shop #: WSC 65536  
   VCID: 3B75F31B29AD6D92C8-4AEC

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags        Labels: 8E0-959-655-94.lbl
   Part No SW: 8E0 959 655 H    HW: 8E0 959 655 H
   Component:    Airbag 9.41  H11 3540  
   Revision: 91H1135    Serial number: 0036N0015SD-  
   Coding: 0032707
   Shop #: WSC 06335 000 00000
   VCID: 3C77F0077FA36AAAC1-8068

   Subsystem 1 - Part No: 8E0 910 339 B
   Component: BF-Gewichtsens. 002 0070

   Subsystem 2 - Serial number: 35SMF         

   Subsystem 3 - Serial number: 0001.01.000000200000000000ÿ†63

   Subsystem 4 - Serial number: 000000ÿ†6332DRB402644C0BMÿ†63

   Subsystem 5 - Serial number: 44C0BMÿ†6342DRB402448BA7Uÿ†63

   Subsystem 6 - Serial number: 48BA7Uÿ†6352ARB400B88DAC1ÿ†63

   Subsystem 7 - Serial number: 88DAC1ÿ†6362ARB400B5A37EXÿ†63

   Subsystem 8 - Serial number: 5A37EXÿ†63729RB400C64922Iÿ†63

   Subsystem 9 - Serial number: 64922Iÿ†63829RB400C6489BYÿ

   Subsystem 10 - Serial number: 6489BYÿ

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel        Labels: 8E0-953-549.lbl
   Part No: 8E0 953 549 Q
   Component: Lenksáulenmodul     0601  
   Coding: 04041
   Shop #: WSC 06335  
   VCID: 418981F34B41074292-4AEC

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments        Labels: 8E0-920-9xx-8EC.lbl
   Part No SW: 8E0 920 982 F    HW: 8E0 920 982 F
   Component: KOMBI+WFS 4     H12 0110  
   Revision: 0110        Serial number: 00000000000000
   Coding: 0023261
   Shop #: WSC 08212 444 85874
   VCID: 3169D133ABE197C262-5140

No fault code found.

-------------------------------------------------------------------------------
Address 25: Immobilizer        Labels: 8E0-920-9xx-8EC.lbl
   Part No SW: 8E0 920 982 F    HW: 8E0 920 982 F
   Component: KOMBI+WFS 4     H12 0110  
   Revision: 0110        Serial number: 00000000000000
   Coding: 0023261
   Shop #: WSC 08212 444 85874
   VCID: 3169D133ABE197C262-5140

No fault code found.

-------------------------------------------------------------------------------
Address 36: Seat Mem. Drvr        Labels: 8E0-959-760.lbl
   Part No: 8E0 959 760 
   Component: Sitzmemory R2 F     0305  
   Coding: 00002
   Shop #: WSC 00000  
   VCID: 71E911333B61D7C222-4B04

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv.        Labels:. 8E0-959-433-MAX.clb
   Part No: 8E0 959 433 BT
   Component: Komfortgerát T7B    3332  
   Coding: 11836
   Shop #: WSC 06335  
   VCID: 040748E714D3D26AF9-4AEC

   Subsystem 1 - Part No: 8E1959801G
   Component: Tõrsteuer.FS BRM 0506  

   Subsystem 2 - Part No: 8E1959802E
   Component: Tõrsteuer.BF BRM 0205  

   Subsystem 3 - Part No: 8E0959801E
   Component: Tõrsteuer.HL BRM 0606  

   Subsystem 4 - Part No: 8E0959802E
   Component: Tõrsteuer.HR BRM 0606  

1 Fault Found:
01366 - Opened Due to Crash Signal 
            35-00 -  - 

-------------------------------------------------------------------------------
Address 55: Headlight Range        Labels: 4F0-910-357.lbl
   Part No SW: 4F0 910 357 E    HW: 4F0 907 357 E
   Component: AFS 1           H01 0010  
   Revision: 00000001    Serial number:               
   Coding: 0000019
   Shop #: WSC 34771 001 1048576
   VCID: 285F3C579B3BD60AB5-807C

   Subsystem 1 - Part No: 8E0 941 329 
   Component: AFS-Modul links H03 0020

   Subsystem 2 - Part No: 8E0 941 329 
   Component: AFS-Modul rechtsH05 0030

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio        Labels: 8E0-035-1xx-56.lbl
   Part No: 8E0 035 195 H
   Component: symphony II PM6    0460   
   Coding: 01065
   Shop #: WSC 73472  
   VCID: 2C57C047DCC3FA2A51-5074

1 Fault Found:
00858 - Connection; Radio Intermediate Frequency (IF) Output to Antenna Amplifier 
            36-00 - Open Circuit

-------------------------------------------------------------------------------
Address 65: Tire Pressure        Labels: 8E0-907-273.lbl
   Part No SW: 8E0 907 273     HW: 8E0 907 273 
   Component: Reifendruck 3   H03 0110  
   Coding: 0062121
   Shop #: WSC 06435 000 00000
   VCID: 69D9795343B12F026A-5122

No fault code found.

-------------------------------------------------------------------------------
Address 77: Telephone        Labels: 8P0-862-335.lbl
   Part No SW: 8P0 862 335 G    HW: 8P0 862 335 G
   Component: FSE_255x BT     H21 0190  
   Revision: 00000001    Serial number: 00000000335603
   Coding: 0001677
   Shop #: WSC 06335 000 00000
   VCID: 3A7BF61F7697549AD3-5140

No fault code found.

End-------------------------(Elapsed Time: 05:51)--------------------------

Code:

              Address 01: Engine       Labels: 06E-910-559-BKH.clb
Control Module Part Number: 8E0 910 559     HW: 8E0 907 559 A
  Component and/or Version: 3.2l V6 FSI         0050
           Software Coding: 01040109190F0120
            Work Shop Code: WSC 06335 000 00000
                      VCID: 6ADB065F45B7241A63-803E
2 Faults Found:

005634 - Power Supply Terminal 30 
               P1602 - 008 - Voltage too Low - Intermittent
             Freeze Frame:
                    Fault Status: 00001000
                    Fault Priority: 2
                    Fault Frequency: 1
                    Reset counter: 38
                    Mileage: 235927 km
                    Time Indication: 0

             Freeze Frame:
                    RPM: 0 /min
                    Mass Air / Rev.: 0.0 mg/str
                    Temperature: 34.5°C
                        Engine Off
                    Load: 0.0 %
                    Speed: 0.0 km/h

012425 - Signal Line for Fuel Pump Electronics 
               P3089 - 007 - Electrical Malfunction - Intermittent
             Freeze Frame:
                    Fault Status: 00000010
                    Fault Priority: 4
                    Fault Frequency: 1
                    Reset counter: 38
                    Mileage: 235926 km
                    Time Indication: 0

             Freeze Frame:
                    RPM: 800 /min
                    Mass Air / Rev.: 190.8 mg/str
                    Temperature: 49.5°C
                        Idle
                    Pressure: 2.1 bar
                    Speed: 0.0 km/h


Readiness: 0110 0101

AIB Wolfgang · Mar 20, 2019

Hello
just a suggestion, did you read this http://wiki.ross-tech.com/wiki/index.php/19545/P3089/012425 in connection with the repair guide ?
That's the way to find the fault

Also, this 005634 - Power Supply Terminal 30
P1602 - 008 - Voltage too Low - Intermittent is described there

Uwe · Mar 20, 2019

Nice first post; welcome! :thumbs:

-Uwe-

Jack@European_Parts · Mar 20, 2019

An unhappy check valve to hold residual regulation at filter dumping to gas tank?

TFSI · Mar 20, 2019

Wotseurba-
To check if the pump is priming, there are few ways you could do that: either you disconnect the fuel supply line to engine and then turn ignition on-fuel should spill out of the hose another way is to leave fuel line disconnected and then open the driver door after long sitting. Please use a container to rap fuel that may pump out and observe safety precautions when doing this. You can also hook an amp clamp to the pump wire and open driver door to check current draw if pump is priming.

But I think Jack may be right with his comment about the check valve being the culprit in this case.

wotseurba · Mar 21, 2019

To all Thank you for the replies.
Specifically:
AIB Wolfgang: I have not been able to reproduce those 2 faults. I am now of the belief that I self-created them when I was testing for pump voltage with electrical connector disconnected, and inadvertently turned on the key.

Jack & TFSI: Agreed the check valve could be worn with the age and mileage of this car allowing quicker bleed down of pressure on the low side. HOWEVER it's my belief that the LP pump SHOULD prime the system either when the driver door is opened, or at the very least when the key is turned to ON. It DOES NOT. No sound from the pump, no voltage to the pump (back probing the connector) during what I believe should be a prime function.

If I energize the pump with external power for 2 seconds, the low side reaches 3.5 BAR pressure (via VCDS), and then the engine starts immediately upon cranking.

I understand the ECM is (supposedly) to send a signal the the pump module when the d. door opens, or the key is placed in ON position. It's obvious something is inhibiting this from happening. I might suspect the pump module, but it merely is a dumb PWM control, and it seemingly functions for both pump testing (via VCDS), and during road testing.

Does anyone have insight on where to begin finding a solution to the no prime issue?

Jack@European_Parts · Mar 21, 2019

The CCM & Central are what send the signal to the FP from the door being opened.........oh look here.

Could there be a bad wire or FP module oh my........

1 Fault Found:
01366 - Opened Due to Crash Signal
35-00 - -

012425 - Signal Line for Fuel Pump Electronics
P3089 - 007 - Electrical Malfunction - Intermittent
Freeze Frame:
Fault Status: 00000010

Hmmmmm

Freeze Frame:
RPM: 800 /min<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Mass Air / Rev.: 190.8 mg/str
Temperature: 49.5°C

Time to RTFB WD!

Run overlay and trace test unless this is induced from you fiddling!

Sterling · Jul 11, 2019

Did this get resolved?

Long cranking to start engine after sitting. ?? Fuel pump prime function

wotseurba

Verified VCDS User

AIB Wolfgang

VCDS Distributor

Uwe

Benevolent Dictator

Jack@European_Parts

Gone But Not Forgotten

TFSI

Verified VCDS User

wotseurba

Verified VCDS User

Jack@European_Parts

Gone But Not Forgotten

Sterling

Verified VCDS User