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2002 A4 1.8t stalling/won't start

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Old 01-21-2010, 02:39 AM
  #1  
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Default 2002 A4 1.8t stalling/won't start

I have been having some issues with my B6 lately that I cannot figure out. I am new to forums, so please bear with me. I will provide all symptoms, related or not and a complete Vag scan. I use this car for work. If you can help me it would be great. I am starting a new sales job in a couple weeks. You can imagine how my stomach turns thinking about this.

For several months, I have noticed a jet engine sound during cold start. I researched and found it was the air pump. Never did anything about that.

About four months ago, I had a coil go bad. Audi replaced it and told me there was a code they couldn't clear for Cat inefficiency. They told me I needed a $1500 Cat, which forced me to tell them to pound sand. I have not yet replaced it on my own.

About two months ago, I started getting an oil pressure warning. I looked on the internet, found out about the sludge problem and cleaned out the oil pan and valve cover. I also replaced the pickup tube for the oil pump. No oil pressure warning after that.

About a month after desludging, things really went wrong. It seems that if I start the car cold, there is no issue. If the engine has been run within the past few hours though, on the first turn of the key, the engine will turn over, but not start. If you turn the key to off and then start it immediatley, it fires right over and off you go.

Now, there seems to be an intermittent stalling issue. I cannot find the rhythm. However, the car at times will flash the check enging and epc lights and the car bucks but keeps going and clears the lights. Sometimes, the car will just shut down on the highway. If you pull over, turn it off and turn it back on, off you go.

Here are my scan results...

Wednesday,20,January,2010,15:42:33:63572
VCDS Version: Release 908.1
Data version: 20091018



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: 8E - Audi A4 B6/B7
Scan: 01 02 03 08 09 0F 11 15 16 17 18 36 37 45 46 55 56 57 65 67
69 75 76 77

VIN: WAULC68E12A106118 Mileage: 145880km/90645miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 06B-909-518-AMB.lbl
Part No SW: 8E0 909 518 F HW: 8E0 909 018
Component: 1.8L R4/5VT G 0001
Coding: 0016751
Shop #: WSC 63351 000 00000

4 Faults Found:
16804 - Catalyst System; Bank 1: Efficiency Below Threshold
P0420 - 002 - Lower Limit Exceeded - Intermittent
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 002 - Lower Limit Exceeded - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded - Intermittent
16685 - Cylinder 1: Misfire Detected
P0301 - 001 - Upper Limit Exceeded - Intermittent
Readiness: 0000 0000

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.lbl
Part No: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 1213
Coding: 0000002
Shop #: WSC 08316 444 54662

1 Fault Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 003 - Mechanical Failure - Intermittent

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.lbl
Part No: 8E0 614 517 A
Component: ABS/ESP allrad 1726
Coding: 04277
Shop #: WSC 08316

1 Fault Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-10 - - - Intermittent

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8E0-820-043.lbl
Part No: 8E0 820 043 G
Component: A4 Klimaautomat 0712
Coding: 00000
Shop #: WSC 63351

1 Fault Found:
65535 - Internal Control Module Memory Error
00-00 - -

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 8E0-907-279-8E2.lbl
Part No: 8E0 907 279 E
Component: int. Lastmodul USA 0305
Coding: 00013
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8E0-959-655-84.lbl
Part No: 8E0 959 655 A
Component: Airbag 8.4E 3000
Coding: 0010607
Shop #: WSC 63351 000 00000

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 8E0-953-549.lbl
Part No: 8E0 953 549 L
Component: Lenksáulenmodul 0308
Coding: 01141
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8E0-920-9xx-8E2.lbl
Part No: 8E0 920 950 H
Component: KOMBI+WEGFAHRS. RB4 D22
Coding: 03200
Shop #: WSC 08316
WAULC68E12A106118 AUZ6Z0A0211902

1 Fault Found:
01314 - Engine Control Module
49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 8E0-951-177.lbl
Part No: 8E0 951 177
Component: Innenraumueberw. 0504
Coding: 00001
Shop #: WSC 00000

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 8E0-959-433-MAX.lbl
Part No: 8E0 959 433 T
Component: Komfortgerát T5B 0617
Coding: 11788
Shop #: WSC 63351

Part No: 8E1959801B
Component: Tõrsteuer.FS BRM 0002

Part No: 8E1959802E
Component: Tõrsteuer.BF BRM 4.22

Part No: 8E0959801A
Component: Tõrsteuer.HL BRM 0002

Part No: 8E0959802A
Component: Tõrsteuer.HR BRM 0002

2 Faults Found:
00962 - Alarm via. Tilt Sensor
35-00 - -
01561 - Left Rear Door
59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D06
Coding: 00060
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8E0-035-1xx-56.lbl
Part No: 8E0 035 195 A
Component: symphony II NP2 0006
Coding: 00001
Shop #: WSC 00000

2 Faults Found:
00858 - Connection; Radio ZF Output to Antenna Amplifier
36-10 - Open Circuit - Intermittent
00878 - Connection to Speaker Front Left
36-10 - Open Circuit - Intermittent

End ---------------------------------------------------------------------


For hahas, I cleared the codes and reran the scan. The misfires cleared, but nothing else. I am only really worried about the occurrences of codes 18258 and 01314. Any thoughts?
Old 01-21-2010, 01:04 PM
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These faults concern me based on your description:

18010 - Power Supply Terminal 30: Voltage too Low ( in Engine only )
and
18258 & 01314 Powertrain Data Bus: Missing Message from ECU ( in Powertrain related modules)

Please check the basics, power and ground connections, battery condition, etc. Also check the connections that had to be loosened during the oil pan removal.

When the car will not start, see if the Engine communicates with VCDS. My concern is the power supply relay for the Ecm. Relays can be intermittent. If you catch this vehicle in the act, say it will not start and you are connected with VCDS...Go to 17 - Inst. cluster, Measuring Block 125 and see if the Engine is on line. This on line status is the internal communication of the cluster and major players: Engine, Transmission and Brake Electronics
Old 01-21-2010, 02:26 PM
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The battery is new. I went through the connections when I got home today. I even opened the housing for the ECU/TCM/Relays. There was one relay that I pushed in all of a millimeter. I ran the codes again and got the same. I cleared the codes, and everything cleared of concern other than Instruments 01314. Then to test if it would start a few hours later, it did, but died a minute later. I turned off the key and turned it back on. I ran a scan and all of the original codes were back.

Could it be the stall/not start that throws the 18258 code?

I talked with a mechanic friend of mine who has some experience with VW/Audi and he thought it was maybe a cam sensor. He is going to give me a good one tomorrow to install and try for a few days. Could that be?
Old 01-21-2010, 02:56 PM
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I just went outside and found the car to not start. The engine value is Engine0, which I guess means it is off line. For Hahas, I tried measuring block 125 on a the automatic transmission group and got Engine0 again. I ran another auto scan before turning the key to off and got this...

Thursday,21,January,2010,16:10:10:63572
VCDS Version: Release 908.1
Data version: 20091018



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: 8E - Audi A4 B6/B7
Scan: 01 02 03 08 09 0F 11 15 16 17 18 36 37 45 46 55 56 57 65 67
69 75 76 77

VIN: WAULC68E12A106118 Mileage: 145910km/90664miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 06B-909-518-AMB.lbl
Part No SW: 8E0 909 518 F HW: 8E0 909 018
Component: 1.8L R4/5VT G 0001
Coding: 0016751
Shop #: WSC 63351 000 00000

2 Faults Found:
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 002 - Lower Limit Exceeded - Intermittent
16804 - Catalyst System; Bank 1: Efficiency Below Threshold
P0420 - 002 - Lower Limit Exceeded - Intermittent
Readiness: 0000 1101

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.lbl
Part No: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 1213
Coding: 0000002
Shop #: WSC 08316 444 54662

1 Fault Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 003 - Mechanical Failure - Intermittent

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.lbl
Part No: 8E0 614 517 A
Component: ABS/ESP allrad 1726
Coding: 04277
Shop #: WSC 08316

2 Faults Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-10 - - - Intermittent
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-10 - - - Intermittent

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8E0-820-043.lbl
Part No: 8E0 820 043 G
Component: A4 Klimaautomat 0712
Coding: 00000
Shop #: WSC 63351

2 Faults Found:
01274 - Air Flow Flap Positioning Motor (V71)
41-10 - Blocked or No Voltage - Intermittent
65535 - Internal Control Module Memory Error
00-00 - -

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 8E0-907-279-8E2.lbl
Part No: 8E0 907 279 E
Component: int. Lastmodul USA 0305
Coding: 00013
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8E0-959-655-84.lbl
Part No: 8E0 959 655 A
Component: Airbag 8.4E 3000
Coding: 0010607
Shop #: WSC 63351 000 00000

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 8E0-953-549.lbl
Part No: 8E0 953 549 L
Component: Lenksáulenmodul 0308
Coding: 01141
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8E0-920-9xx-8E2.lbl
Part No: 8E0 920 950 H
Component: KOMBI+WEGFAHRS. RB4 D22
Coding: 03200
Shop #: WSC 08316
WAULC68E12A106118 AUZ6Z0A0211902

1 Fault Found:
01314 - Engine Control Module
49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 8E0-951-177.lbl
Part No: 8E0 951 177
Component: Innenraumueberw. 0504
Coding: 00001
Shop #: WSC 00000

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 8E0-959-433-MAX.lbl
Part No: 8E0 959 433 T
Component: Komfortgerát T5B 0617
Coding: 11788
Shop #: WSC 63351

Part No: 8E1959801B
Component: Tõrsteuer.FS BRM 0002

Part No: 8E1959802E
Component: Tõrsteuer.BF BRM 4.22

Part No: 8E0959801A
Component: Tõrsteuer.HL BRM 0002

Part No: 8E0959802A
Component: Tõrsteuer.HR BRM 0002

5 Faults Found:
01134 - Alarm Horn (H12)
49-10 - No Communications - Intermittent
01703 - Footwell Lighting; Right (W10)
29-10 - Short to Ground - Intermittent
01697 - Footwell Lighting; Rear Right (W46)
29-10 - Short to Ground - Intermittent
01696 - Footwell Lighting; Rear Left (W45)
29-10 - Short to Ground - Intermittent
01561 - Left Rear Door
59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D06
Coding: 00060
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8E0-035-1xx-56.lbl
Part No: 8E0 035 195 A
Component: symphony II NP2 0006
Coding: 00001
Shop #: WSC 00000

1 Fault Found:
00858 - Connection; Radio ZF Output to Antenna Amplifier
36-10 - Open Circuit - Intermittent

End ---------------------------------------------------------------------
Thursday,21,January,2010,16:27:53:63572
VCDS Version: Release 908.1
Data version: 20091018


Chassis Type: 8E - Audi A4 B6/B7
Scan: 01 02 03 08 09 0F 11 15 16 17 18 36 37 45 46 55 56 57 65 67
69 75 76 77

VIN: WAULC68E12A106118 Mileage: 145910km/90664miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 06B-909-518-AMB.lbl
Part No SW: 8E0 909 518 F HW: 8E0 909 018
Component: 1.8L R4/5VT G 0001
Coding: 0016751
Shop #: WSC 63351 000 00000

No fault code found.
Readiness: 0110 1101

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.lbl
Part No: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 1213
Coding: 0000002
Shop #: WSC 08316 444 54662

No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.lbl
Part No: 8E0 614 517 A
Component: ABS/ESP allrad 1726
Coding: 04277
Shop #: WSC 08316

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8E0-820-043.lbl
Part No: 8E0 820 043 G
Component: A4 Klimaautomat 0712
Coding: 00000
Shop #: WSC 63351

1 Fault Found:
65535 - Internal Control Module Memory Error
00-00 - -

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 8E0-907-279-8E2.lbl
Part No: 8E0 907 279 E
Component: int. Lastmodul USA 0305
Coding: 00013
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8E0-959-655-84.lbl
Part No: 8E0 959 655 A
Component: Airbag 8.4E 3000
Coding: 0010607
Shop #: WSC 63351 000 00000

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 8E0-953-549.lbl
Part No: 8E0 953 549 L
Component: Lenksáulenmodul 0308
Coding: 01141
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8E0-920-9xx-8E2.lbl
Part No: 8E0 920 950 H
Component: KOMBI+WEGFAHRS. RB4 D22
Coding: 03200
Shop #: WSC 08316
WAULC68E12A106118 AUZ6Z0A0211902

1 Fault Found:
01314 - Engine Control Module
49-10 - No Communications - Intermittent

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 8E0-951-177.lbl
Part No: 8E0 951 177
Component: Innenraumueberw. 0504
Coding: 00001
Shop #: WSC 00000

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 8E0-959-433-MAX.lbl
Part No: 8E0 959 433 T
Component: Komfortgerát T5B 0617
Coding: 11788
Shop #: WSC 63351

5 Faults Found:
01134 - Alarm Horn (H12)
49-10 - No Communications - Intermittent
01703 - Footwell Lighting; Right (W10)
29-10 - Short to Ground - Intermittent
01697 - Footwell Lighting; Rear Right (W46)
29-10 - Short to Ground - Intermittent
01696 - Footwell Lighting; Rear Left (W45)
29-10 - Short to Ground - Intermittent
01561 - Left Rear Door
59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D06
Coding: 00060
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8E0-035-1xx-56.lbl
Part No: 8E0 035 195 A
Component: symphony II NP2 0006
Coding: 00001
Shop #: WSC 00000

1 Fault Found:
00858 - Connection; Radio ZF Output to Antenna Amplifier
36-10 - Open Circuit - Intermittent

End ---------------------------------------------------------------------
Thursday,21,January,2010,18:55:43:63572
VCDS Version: Release 908.1
Data version: 20091018



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Chassis Type: 8E - Audi A4 B6/B7
Scan: 01 02 03 08 09 0F 11 15 16 17 18 36 37 45 46 55 56 57 65 67
69 75 76 77

VIN: WAULC68E12A106118 Mileage: 145910km/90664miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: None
Component:
Shop #: WSC 00000 000 00000

No Faults Found
or DTCs not supported by controller
or a communication error occurred

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.lbl
Part No: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 1213
Coding: 0000002
Shop #: WSC 08316 444 54662

1 Fault Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 003 - Mechanical Failure

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.lbl
Part No: 8E0 614 517 A
Component: ABS/ESP allrad 1726
Coding: 04277
Shop #: WSC 08316

2 Faults Found:
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-00 - -
18258 - Powertrain Data Bus: Missing Message from ECU
P1850 - 35-00 - -

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 8E0-820-043.lbl
Part No: 8E0 820 043 G
Component: A4 Klimaautomat 0712
Coding: 00000
Shop #: WSC 63351

1 Fault Found:
65535 - Internal Control Module Memory Error
00-00 - -

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 8E0-907-279-8E2.lbl
Part No: 8E0 907 279 E
Component: int. Lastmodul USA 0305
Coding: 00013
Shop #: WSC 63351

1 Fault Found:
00532 - Supply Voltage B+
52-10 - Supply Voltage Too High - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 8E0-959-655-84.lbl
Part No: 8E0 959 655 A
Component: Airbag 8.4E 3000
Coding: 0010607
Shop #: WSC 63351 000 00000

No fault code found.

-------------------------------------------------------------------------------
Address 16: Steering wheel Labels: 8E0-953-549.lbl
Part No: 8E0 953 549 L
Component: Lenksáulenmodul 0308
Coding: 01141
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 8E0-920-9xx-8E2.lbl
Part No: 8E0 920 950 H
Component: KOMBI+WEGFAHRS. RB4 D22
Coding: 03200
Shop #: WSC 08316
WAULC68E12A106118 AUZ6Z0A0211902

1 Fault Found:
01314 - Engine Control Module
49-00 - No Communications

-------------------------------------------------------------------------------
Address 45: Inter. Monitor Labels: 8E0-951-177.lbl
Part No: 8E0 951 177
Component: Innenraumueberw. 0504
Coding: 00001
Shop #: WSC 00000

No fault code found.

-------------------------------------------------------------------------------
Address 46: Central Conv. Labels: 8E0-959-433-MAX.lbl
Part No: 8E0 959 433 T
Component: Komfortgerát T5B 0617
Coding: 11788
Shop #: WSC 63351

Part No: 8E1959801B
Component: Tõrsteuer.FS BRM 0002

Part No: 8E1959802E
Component: Tõrsteuer.BF BRM 4.22

Part No: 8E0959801A
Component: Tõrsteuer.HL BRM 0002

Part No: 8E0959802A
Component: Tõrsteuer.HR BRM 0002

5 Faults Found:
01134 - Alarm Horn (H12)
49-10 - No Communications - Intermittent
01703 - Footwell Lighting; Right (W10)
29-10 - Short to Ground - Intermittent
01697 - Footwell Lighting; Rear Right (W46)
29-10 - Short to Ground - Intermittent
01696 - Footwell Lighting; Rear Left (W45)
29-10 - Short to Ground - Intermittent
01561 - Left Rear Door
59-10 - Can't Unlock - Intermittent

-------------------------------------------------------------------------------
Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D06
Coding: 00060
Shop #: WSC 63351

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio Labels: 8E0-035-1xx-56.lbl
Part No: 8E0 035 195 A
Component: symphony II NP2 0006
Coding: 00001
Shop #: WSC 00000

1 Fault Found:
00858 - Connection; Radio ZF Output to Antenna Amplifier
36-10 - Open Circuit - Intermittent

End ---------------------------------------------------------------------

there is some weird new stuff.
Old 01-21-2010, 08:27 PM
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In that last scan you have a communication error to the Engine. The "0" is a no communication as well.

I would want to verify power to the module. Power supply relay, etc. You mentioned you were under the hood at the Ecm box. Were there several relays and fuses in that box? Check your repair manual, but I believe that's where the Ecm relay lives.

It is possible that the module is faulty, but that is a last resort.
Old 01-22-2010, 03:15 AM
  #6  
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I brought my car to work today to have my buddy look at the connections, to see if there is something I am missing. It appeared (on my 60 mile drive in) that the ECM shut down momentarily a few times on the ride. THe EPC and CEL flashed and there was a short loss of power. There did not seem to be a rhythm to it though. I am going to have him replace the ECM relay, which is in that box.

Is there any sensor that could shut down the ECM entirely? If I am reading the wiring diagram right, it seems only the battery, ignition switch, relay and ECM itself(and all connections between) control the power to the ECM. I guess I feel at this point, the possibilities are; bad ground, bad connections between battery and ECM, bad ignition switch, bad relay or bad ECM. Does that cover everything?
Old 01-22-2010, 05:59 AM
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That sounds like it.

If the ignition switch or main vehicle power or grounds were faulty, I would think there would be several modules off line or with voltage faults. Surely check all of the basics, and for any evidence of aftermarket components. Examples including remote starters, boost controllers, anything tapped into the wiring that shouldn’t be.

If that all checks out okay and the power supply relay doesn’t resolve it possibly pin check the entire Ecm harness connector. The difficult thing there is catching the problem in the act and having the test equipment ready to test all of that. Surely an intermittent ground could do something similar.

In general no single sensor will cause an Ecm to go off line. Yes, some will cause intermittent no starts and stalling. This doesn’t seem to be the case with the lack of communication.
Old 01-22-2010, 06:10 AM
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Thanks Dana. I can make the problem happen, so I am not concerned about the timing. All I have to do is run the car until running temp. Turn it off. And try to start it ~2 hours later. That rhythm I have caught up to.

I will try to get the relay today. Hopefully that does it. My mechanic has the car in the air right now, making sure no connections are undone.

I agree that the ignition switch ground being no good is not likely the issue. So many other things would visibily not work.

As soon as I get this relay in, I will get back to you.
Old 01-23-2010, 08:35 AM
  #9  
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My mechanic found nothing. He could not duplicate the problem. I am working it out now, with a jumper in place of the relay. I am optimistic at this point. I will get back shortly.
Old 01-24-2010, 09:49 AM
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Problem solved!!! I made a jumper to test the ECM relay, which actually powers the fuel pump relay as well. It seems the fuel pump is double relayed.

Anyhow, the jumper didn't work. I made a simple two lead wire, and the relay I was trying to replace is more complex than that. However, I was certain it was the relay, so I ordered one at my dealer, as they had none in stock. They not having it in stock, made me look on the internet for the part, by number. That part number led me to several forums where people were having the same physical symptoms and VAG results. I took the original relay and soldered the contacts together. I put that relay in and bang, there it was.

Problem solved, sort-of. With the contacts soldered together, there is a constant circuit to the cooling fans. Until my new ($63) relay comes in, I will have to disconnect the battery everytime I shut the car down. I could care less however, as I do not have to pay for a new computer.

Dana, thanks for your help. I bought my hex+usb-can dongle and software license for this issue. This purchase turned out to be well worth the money I paid already. Now I am going to make my windows roll down with the fob.


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