1.2 12V petrol Engine cut out, cam sensor fault, then popped hose

[jimbof]

My brother-in-laws 1.2 12V CGPB 2011 Polo cut out on him the other day in traffic, he couldn't start restart (several attempts made), so he was pushed to a car park. I just got round to looking at it for him with VCDS - several faults logged, cleared, attempted to restart which failed and the only remaining fault after restart was cam sensor signal implausible. So today I picked up a new sensor and went over to fit it.

Fitted the sensor, re-started; couple of cranks, a loud POP/BANG and a bit of smoke under the hood. At first I suspected some electrical problem - but on investigation the bang was a hose at the back of the engine exploding - a centre section snapping clean out.

These are pictures of the broken hose and what it was attached to:
https://drive.google.com/file/d/0B-_YzK ... sp=sharing
https://drive.google.com/file/d/0B-_YzK ... sp=sharing

I do most things on my own 1.9PD Superb (including cam belt changes) - but I only really know my way round that engine and could really appreciate some advice and pointers. I've not dared try to re-start it since the hose popped as I figure it may not be in a good way... or could it just have popped as a result of too much unburnt fuel somewhere from many previous crank attempts?

Help very gratefully received. Thanks

The engine codes before and after clearing:

Code: Select all

Address 01: Engine (J623-CGPB)       Labels: 03E-906-019-CGP.clb
   Part No SW: 03E 906 019 M    HW: 03E 906 019 B
   Component: SIMOS11.1     H03 9877  
   Revision: --H03---    Serial number:               
   Coding: 00110010000400080000
   Shop #: WSC 31414 790 50316
   ASAM Dataset: EV_ECM12MPI02103E906019M 001010
   ROD: EV_ECM12MPI02103E906019A.rod
   VCID: 2E59078E71E2E0314B-807A

6 Faults Found:
6351 - Cylinder 2 
          P0302 00 [101] - Misfire Detected
          Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 19
                    Mileage: 120873 km
                    Date: 2017.05.10
                    Time: 15:21:52

                    Engine speed: 2893.00 /min
                    Normed load value: 96.1 %
                    Vehicle speed: 36 km/h
                    Coolant temperature: 88 ∞C
                    Intake air temperature: 42 ∞C
                    Ambient air pressure: 990 mbar
                    Voltage terminal 30: 13.609 V
                    Unlearning counter according OBD: 40
                    Number of cylinder 2 misfires in drive cycle-Misfires cylinder 4 from engine start to engine stop: 74
                    Misfire detection: counter in driving cycle-CTR_MIS_TOT_DC: 74
                    Misfire sum counter: carb A-MIS_SUM_A: 0
                    Misfire sum counter-Misfires all cylinders per 1000 rpm: 74

6319 - MAP/MAF <-> Throttle Position Correlation 
          P0068 00 [104] - -
          Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 9
                    Mileage: 123481 km
                    Date: 2017.06.24
                    Time: 11:42:43

                    Engine speed: 2656.00 /min
                    Normed load value: 40.8 %
                    Vehicle speed: 96 km/h
                    Coolant temperature: 89 ∞C
                    Intake air temperature: 39 ∞C
                    Ambient air pressure: 1010 mbar
                    Voltage terminal 30: 13.812 V
                    Unlearning counter according OBD: 40
                    Absolute intake pressure: 43 kPa abs
                    Intake manifold pressure: target value-MAP_SP: 548.50 hPa
                    Reduced_throttle valve surface_active_total correction-AR_RED_SUM_COR_ACT_REL: 42.085 %
                    Throttle valve position: actual value-Throttle valve angle: 8.607 ∞

6326 - Leak in Air Intake System 
          P2279 00 [096] - -
          Intermittent - Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 123649 km
                    Date: 2017.06.27
                    Time: 07:44:59

                    Engine speed: 1930.00 /min
                    Normed load value: 91.8 %
                    Vehicle speed: 24 km/h
                    Coolant temperature: 42 ∞C
                    Intake air temperature: 20 ∞C
                    Ambient air pressure: 740 mbar
                    Voltage terminal 30: 14.116 V
                    Unlearning counter according OBD: 38
                    Absolute intake pressure: 71 kPa abs
                    Intake manifold pressure: target value-MAP_SP: 700.82 hPa
                    Reduced_throttle valve surface_active_total correction-AR_RED_SUM_COR_ACT_REL: 44.446 %
                    Throttle valve position: actual value-Throttle valve angle: 13.334 ∞

11836 - Cylinder Disabling 
          P130A 00 [096] - -
          Intermittent - Not Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 28
                    Mileage: 120873 km
                    Date: 2017.05.10
                    Time: 15:21:53

                    Engine speed: 2301.00 /min
                    Normed load value: 31.0 %
                    Vehicle speed: 36 km/h
                    Coolant temperature: 88 ∞C
                    Intake air temperature: 42 ∞C
                    Ambient air pressure: 990 mbar
                    Voltage terminal 30: 13.507 V
                    Unlearning counter according OBD: 40
                    Time since engine start: 0 s
                    Engine torque: 134.75000 Nm
                    Accelerator pedal travel-Accelerator position: 79.00 %
                    Ignition angle of current cylinder: actual value-Ignition angle: actual: 0.750 ∞

10976 - Camshaft Position Sensor (G40) 
          P0341 00 [108] - Implausible Signal
          Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 17
                    Mileage: 123469 km
                    Date: 2000.00.00
                    Time: 00:00:00

                    Engine speed: 151.00 /min
                    Normed load value: 100.0 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 92 ∞C
                    Intake air temperature: 36 ∞C
                    Ambient air pressure: 990 mbar
                    Voltage terminal 30: 11.882 V
                    Unlearning counter according OBD: 40
                    Time since engine start: 0 s
                    Engine torque: 125.31250 Nm
                    Accelerator pedal travel-Accelerator position: 0.00 %
                    Ignition angle of current cylinder: actual value-Ignition angle: actual: 2.625 ∞

10980 - Camshaft Position Sensor (G40) 
          P0341 00 [237] - Implausible Signal
          MIL ON - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 19
                    Mileage: 121805 km
                    Date: 2017.05.25
                    Time: 18:06:47

                    Engine speed: 1000.00 /min
                    Normed load value: 59.2 %
                    Vehicle speed: 0 km/h
                    Coolant temperature: 88 ∞C
                    Intake air temperature: 33 ∞C
                    Ambient air pressure: 1000 mbar
                    Voltage terminal 30: 11.476 V
                    Unlearning counter according OBD: 40
                    Time since engine start: 0 s
                    Engine torque: 136.12500 Nm
                    Accelerator pedal travel-Accelerator position: 33.11 %
                    Ignition angle of current cylinder: actual value-Ignition angle: actual: 3.000 ∞

Readiness: 0000 0000

Code: Select all

-------------------------------------------------------------------------------
Address 01: Engine (J623-CGPB)       Labels: 03E-906-019-CGP.clb
   Part No SW: 03E 906 019 M    HW: 03E 906 019 B
   Component: SIMOS11.1     H03 9877  
   Revision: --H03---    Serial number:               
   Coding: 00110010000400080000
   Shop #: WSC 31414 790 50316
   ASAM Dataset: EV_ECM12MPI02103E906019M 001010
   ROD: EV_ECM12MPI02103E906019A.rod
   VCID: 2E59078E71E2E0314B-807A

1 Fault Found:
10980 - Camshaft Position Sensor (G40) 
          P0341 00 [100] - Implausible Signal
          Intermittent - Not Confirmed - Tested Since Memory Clear
Readiness: 0110 0101

[alexperkins]

That’s the feed from the crankcase into the breather (PCV). The only reason that would go pop is excessive oil pressure causing a sudden surge in crankcase pressure implying there’s either an issue with the PCV or an oil related issue

[RUM4MO]

I think that you should now check the engine timing in case the chain has jumped a tooth or two, that sudden increase in crankcase pressure could have come from a nasty internal engine failure!

[jimbof]

Thanks for the replies - I didn't see them as the thread was my first post and it was awaiting moderation.

That’s the feed from the crankcase into the breather (PCV). The only reason that would go pop is excessive oil pressure causing a sudden surge in crankcase pressure implying there’s either an issue with the PCV or an oil related issue

Might an oil overfill cause that kind of thing on the crankcase breather?

I think that you should now check the engine timing in case the chain has jumped a tooth or two, that sudden increase in crankcase pressure could have come from a nasty internal engine failure!

Having read a little around this engine it does sound like they don't have a brilliant chain setup. Is this an interference engine like my 1.9PD? - i.e. tooth jump means lights out time?

[alexperkins]

Overfilled oil can cause excessive oil pressure, yes.

[jimbof]

Got some more info out of the patients owner... Apparently it hadn't been running right for a few days and had the oil light on despite having enough oil, so he drove it for a fair bit and then when it "stopped in traffic" it made a hell of a racket. If I had known that I wouldn't have wasted my time... Sounds like he's had some timing component failure resulting in the oil pump not doing its duty.

I don't know how anyone who is a pro mechanic keeps their composure.

[RUM4MO]

Yes it will be an interference engine, so not good, and yes if it has suffered something that has been causing oil pressure to be too low then the chain tensioner would not be best pleased, which would leave the chain in a spot of trouble other than it not getting lubricated!
I'm sure that you will keep in touch with its progress/prognoses!