Hello all. I have a Fabia 1.4 16V petrol engine BBZ (2006). My son uses it to commute about 50 miles each day. In the past couple of weeks he gets the following symptoms:

When stationary and idling, the engine revs start fluctuating and if the engine isn't given any gas the engine cuts out completely. It often doesn't restart. Sometimes, if left for 20 minutes it will restart. I've run the car through VCDS and obtained the following output (I've removed any module output with no fault codes):

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Chassis Type: 6Y (01 - Fabia)
Scan: 01 03 08 09 15 17 19 25 44 46 56 76
 
VIN: xxxxxxxxxx Mileage: 138120km-85823miles
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Address 01: Engine        Labels: 036-906-034-APE.lbl
   Part No: 036 906 034 DF
   Component:  MARELLI 4MV G      5954  
   Coding: 00071
   Shop #: WSC 13765  
   VCID: 59B951E2C3456F4E34-4B34
   TMBMD46Y274094010     SKZ7Z0F3857289

3 Faults Found:
17848 - EGR Valve (N18) 
            P1440 - 35-10 - Open Circuit - Intermittent
17586 - Linear O2 Sensor; Pump Current 
            P1178 - 35-10 - Open Circuit - Intermittent
17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1 
            P1196 - 35-10 - Electrical Malfunction - Intermittent
Readiness: 0000 0000

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Address 08: Auto HVAC        Labels: 6Q0-820-045.lbl
   Part No: 6Y0 820 045 
   Component: Klimaanlage        X0840  
   VCID: 72EB064E3EF33C1615-5124

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

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Address 09: Cent. Elect.        Labels:. 6Qx-937-049-C.lbl
   Part No: 6Q1 937 049 D
   Component: 0000 BN-SG.         1S34  
   Coding: 25774
   Shop #: WSC 13765  
   VCID: 3C77E8762C37BA660F-5142

1 Fault Found:
01598 - Drive Battery Voltage 
            07-10 - Signal too Low - Intermittent

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Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 1C0 909 601 A
   Component: 11 AIRBAG VW51      0009  
   Coding: 12593
   Shop #: WSC 13765  
   VCID: 1E3302FE9AEBC87601-5124

1 Fault Found:
00532 - Supply Voltage B+ 
            07-10 - Signal too Low - Intermittent

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Address 76: Park Assist        Labels: 6Y6-919-283.lbl
   Part No: 6Y6 919 283 A
   Component: Einparkhilfe        0001  
   Coding: 00103
   Shop #: WSC 13765  
   VCID: 46838A9E62FBF0B669-5106

3 Faults Found:
01546 - Sensor for Parking Aid; Rear Mid-Left (G204) 
            28-10 - Short to Plus - Intermittent
01548 - Sensor for Parking Aid; Rear Right (G206) 
            28-10 - Short to Plus - Intermittent
01548 - Sensor for Parking Aid; Rear Right (G206) 
            31-10 - Open or Short to Ground - Intermittent

End-------------------------(Elapsed Time: 02:01)--------------------------

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If I clear the fault codes then the car goes back to normal for a couple of hours of driving. Previous fault code readings have given:

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Chassis Type: 6Y (5J - Skoda Fabia (2007 > 2010))
Scan: 01 02 03 08 09 15 16 17 19 25 37 44 46 55 56 76 77
 VIN: xxxxxxx   Mileage: 136890km-85059miles
-------------------------------------------------------------------------------
Address 01: Engine        Labels: 036-906-034-APE.lbl
   Part No: 036 906 034 DF
   Component:  MARELLI 4MV G      5954  
   Coding: 00071
   Shop #: WSC 13765  
   VCID: 59B951E2C3456F4E34-4B34
   TMBMD46Y274094010     SKZ7Z0F3857289

1 Fault Found:
17848 - EGR Valve (N18) 
            P1440 - 35-10 - Open Circuit - Intermittent
Readiness: 0000 0000

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Address 08: Auto HVAC        Labels: 6Q0-820-045.lbl
   Part No: 6Y0 820 045 
   Component: Klimaanlage        X0840  
   VCID: 72EB064E3EF33C1615-5124

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

-------------------------------------------------------------------------------
Address 09: Cent. Elect.        Labels:. 6Qx-937-049-C.lbl
   Part No: 6Q1 937 049 D
   Component: 0000 BN-SG.         1S34  
   Coding: 25774
   Shop #: WSC 13765  
   VCID: 3C77E8762C37BA660F-5124

1 Fault Found:
01598 - Drive Battery Voltage 
            07-10 - Signal too Low - Intermittent

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Address 15: Airbags        Labels: 6Q0-909-605-VW5.lbl
   Part No: 1C0 909 601 A
   Component: 11 AIRBAG VW51      0009  
   Coding: 12593
   Shop #: WSC 13765  
   VCID: 1E3302FE9AEBC87601-5124

1 Fault Found:
00532 - Supply Voltage B+ 
            07-10 - Signal too Low - Intermittent

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Address 46: Central Conv.        Labels:. 6Q0-959-433.clb
   Part No: 6Q0 959 433 E
   Component: 60 Komfortgerát     0002  
   Coding: 00018
   Shop #: WSC 13765  
   VCID: 3D71E572372DB36E38-4ACE

1 Fault Found:
01135 - Interior Monitoring Sensors 
            36-10 - Open Circuit - Intermittent

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Address 76: Park Assist        Labels: 6Y6-919-283.lbl
   Part No: 6Y6 919 283 A
   Component: Einparkhilfe        0001  
   Coding: 00103
   Shop #: WSC 13765  
   VCID: 46838A9E62FBF0B669-5106

2 Faults Found:
01546 - Sensor for Parking Aid; Rear Mid-Left (G204) 
            28-00 - Short to Plus
01548 - Sensor for Parking Aid; Rear Right (G206) 
            28-10 - Short to Plus - Intermittent

End-------------------------(Elapsed Time: 03:50)--------------------------

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I had one VCDS log that give such errors as:

01314 - Engine Control Module (Brakes)
            004 - No Signal/Communication - Intermittent

01314 - Engine Control Module (Cent. Elect.) 
            49-10 - No Communications - Intermittent

01314 - Engine Control Module (Instruments)
            49-10 - No Communications - Intermittent

01314 - Engine Control Module (CAN Gateway)
            49-10 - No Communications - Intermittent

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I'm thinking this is an ECU problem but don't want to spend money if that really isn't it. Two faults that seem plausible are the 

17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1 
            P1196 - 35-10 - Electrical Malfunction - Intermittent
17586 - Linear O2 Sensor; Pump Current 
            P1178 - 35-10 - Open Circuit - Intermittent

RossTech wiki suggests that a broken ECU could also be the cause of these.

 

Any suggestions?

 

I would start here: 

 

And then inspect the brake servo vacuum hose carefully.

 

 

Thank you for the comment. I've come across the vacuum hose problem before - indeed I've replaced it and that is still good. The battery light comes on and goes out as described. Could the "non blue" wire breakage cause these faults?

 

I have found a second hand ECU unit on ebay for £69. I've got Vagcom so I believe I could swap the ECU's over. I was told by the ebay merchant that "you won't be able to do it with Rosstech unless you have the PIN code for the car and will be able to extract the PIN out of the new ECU". I have no idea if this is correct or not.

 

Any further thoughts?

2 minutes ago, jverdicchio said:

I have no idea if this is correct or not.

 

That is correct.

 

I would look into the EGR fault myself, that can certainly cause a cutting out condition.

 

Lambda probe issues are also common place.

Thanks for the confirmation on the PIN. We've had the EGR fault since we had the car (a couple of years). A warning light comes on, stays on for a while and then goes off again. It's never caused this issue. i.e. I've checked the fault codes and we've had that EGR valve fault and the car drives just fine.

 

The lambda probe seems like the next investigation.  Is this normally a "replace the probe" fix?

I would certainly replace the lambda probe if it's the original one, after all this time it won't be accurate any more and is probably faulty anyway.

You should try running with the EGR valve unplugged in the meantime and see if the problem persists.