Any ideas what could be happening here, folks?

My Octavia VRS had a 'funny turn' tonight. The car was loaded with shopping and people, travelling slightly uphill, foot to the floor in 5th so was under heavy load at about 3000 rpm when the CEL started flashing, the car stuttered, the DV chattered. I eased off and everything was fine. Back home I found a P0300 and P0304 logged.

000768 - Random/Multiple Cylinder Misfire Detected

P0300 - 001 - Upper Limit Exceeded

Freeze Frame:

Fault Status: 01100001

Fault Priority: 2

Fault Frequency: 1

Mileage: 89538 km

Time Indication: 0

Date: 2000.00.00

Time: 20:22:15

Freeze Frame:

RPM: 3075 /min

Load: 92.1 %

Speed: 104.0 km/h

Temperature: 90.0°C

Temperature: 9.0°C

Absolute Pres.: 990.0 mbar

Voltage: 14.351 V

000772 - Cylinder 4: Misfire Detected

P0304 - 001 - Upper Limit Exceeded

Freeze Frame:

Fault Status: 01100001

Fault Priority: 2

Fault Frequency: 1

Mileage: 89538 km

Time Indication: 0

Date: 2000.00.00

Time: 20:22:15

Freeze Frame:

RPM: 3075 /min

Load: 92.1 %

Speed: 104.0 km/h

Temperature: 90.0°C

Temperature: 9.0°C

Absolute Pres.: 990.0 mbar

Voltage: 14.351 V

Readiness: 0000 0000

My initial feeling was that it would be the usual coil pack / plug problem. However, a recent Rolling Road day showed some funky AFR/fuelling going on...

Any ideas if something else could be going on here???

Any ideas appreciated!

Edited 24 November, 201015 yr by muckipup

First sign before my old engine went pop.

Would be worth checking coilpacks and plugs regardless, that would be my first port of call.

Edited 24 November, 201015 yr by Harry_vRS

First sign before my old engine went pop.

Would be worth checking coilpacks and plugs regardless, that would be my first port of call.

Jeeez Harry - you know how to cheer a boy up! Well, I'm sticking a K04 on it in 2 weeks time so could be 'kill or cure'

Yeh just be careful with it. I'd maybe get JKM to do a compression test on the block whilst they have it. Reason my old engine went was because cylinders 2 and 4 lost compression.

Yeh just be careful with it. I'd maybe get JKM to do a compression test on the block whilst they have it. Reason my old engine went was because cylinders 2 and 4 lost compression.

Cheers

That is the exact same fault i had when my coil pack went.

Easy way to test is move the coil pack from cylinder 4 to another cylinder and see if the fault occurs again on the new cylinder.

I have Spare coil packs if you fancy a trip to Folkestone

Also im about 45 mins from Portsmouth during the week so can come to you if you wish

Also im about 45 mins from Portsmouth during the week so can come to you if you wish

I appreciate the offer Carl. You know what - JKM are doing my service and cambelt in a week and a half along with the K04. I'll pick up a coil pack or two then...if one hasn't gone already, it soon will with these things

Edited 26 November, 201015 yr by muckipup

Chipped? Which ECU P/N and Software version do you have at the moment.

Chipped? Which ECU P/N and Software version do you have at the moment.

Hi Sebastian,

Yes, I am remapped. I am not sure if I am looking at the right information but I see: F103 S1.57 VAG TFSI MED 9.1/5 if that makes sense.

And in a VCDS log under engine:

Address 01: Engine Labels: 06F-907-115-AXX.lbl

Part No SW: 1Z0 907 115 D HW: 8P0 907 115 B

Component: 2.0l R4/4V TFSI 0010

Revision: 5BH16--- Serial number: SKZ7Z0G4390402

Coding: 0203000318070160

Shop #: WSC 66565 257 00032

VCID: 364515093835

If not, could you let me know how I find this on VCDS, please?

Best wishes,

Dave

Edited 26 November, 201015 yr by muckipup

Your ECU S/W version is 1Z0-907-115-D @ 0010. The actual version number is 0010, but that is only relevant in combination with the software part number.

I was hoping you had an older one but no, so no updates available which brings us back to finding the fault the hard way.

Which values do you have in Meas. Value Block (MVB) 032?

Did you look at the timing retardation for each cylinder?

Did you try exchanging the ignition coil from cylinder 4 with another one to see if the fault moves as well?

Your ECU S/W version is 1Z0-907-115-D @ 0010. The actual version number is 0010, but that is only relevant in combination with the software part number.

I was hoping you had an older one but no, so no updates available which brings us back to finding the fault the hard way.

Which values do you have in Meas. Value Block (MVB) 032?

Did you look at the timing retardation for each cylinder?

Did you try exchanging the ignition coil from cylinder 4 with another one to see if the fault moves as well?

Hi Sebastian,

The fuel trim is -1.8% and +5.1% which is not bad (although it used be close to zero a few months ago)

The timing retardation was zero to minimal across all four cylinders. I would post up logs but it would just be looking at columns of '0's except when timing pull went to about 2-3 mid-range doing the red line run. (In fact, I would have expected a bit more timing pull as I believe some remappers introduce this to squeeze out a bit more torque).

I did see misfire in cylinder 4 but only occasionally and in 3 very occasionally so I replaced those coilpacks and will test things out again tomorrow.

I do see a couple of curious things - engine load actual drops off vs. expected mid-range revs and the lambda actual vs. requested tracks very closely when accelerating or constant revs (including red line run) but when coming off the throttle at any speed actual lambda goes to 1.99 consistently and constantly whereas specified lamba remains at 0.95 - 1 :wonder:

Does anyone know if that is to be expected?

Cheers