07 DSG bogging down under acceleration

[rubdub]

Hey guys,

Took the car out for a little spin after a few days of no driving lockdown. Once the engine had warmed up I gave it a little gas to stretch her legs a bit and the car suddenly bogged down and the engine check light flashed for a few seconds and went out. At low revs it's driving totally normal, but getting that stutter under load. I had noticed in the past the car would shudder slightly when idling after a cold start.

Checked my OBD for codes and got the following:
Trouble codes:
        P0300 - Random/Multiple Cylinder Misfire Detected Upper limit exceeded
            static
        P0304 - Cyl.4 Misfire Detected Upper limit exceeded
            static

So obviously signs are pointing towards a misfire, but just wondering if there is anything else I should be checking aside from sparks and coil?
Reading other posts on here I am slightly/incredibly worried it could be cam follower and HPFP being busted, so going to check them too. If it is these two just hoping I caught them early enough.

When I have the pump and follower out whats the best way to turn the cam to inspect the lobe?

Thanks in advance!

[Adrian 200bhp]

Garage recommended i had cam follower changed when i had service done and good job they said about as it was just on its way out. Heard somewhere these should be changed every 20,000 miles.

[rubdub]

So I took off the fuel pump and cam follower, and surprisingly they both look in quite good condition.

Having owned the car for the past two years and the previous owner also had never changed it or had any record of it being changed I was really expecting the worst when I took this out.

Don't have a huge amount of experience with VAG engines from before this period so would be great if someone could confirm that the cam follower and lobe are in ok condition?







https://www.flickr.com/photos/188145521@N05/with/49825621538/

My next question is how do I rotate the cam lobe on a DSG? 

[ROH ECHT]

Can you not see one peak with the hpfp removed? Even if you cannot, the area between the peaks may be grooved slightly if the peaks have been damaged in the past. If tuned with the hpfp upgrade, CF change is between 10k and 20k miles. Otherwise it should last much longer. The owner must determine CF life when "tuned/no hpfp upgrade" because rail pressure target will differ, as well as the driver habit to increase throttle position which requires more rail pressure. So, driving habits.

Another way is to remove the vacuum pump; https://blog.fcpeuro.com/hs-fs/hubfs/Images/Blog/active/Humble-Mechanic-Brake-Vacuum-Pump/09-hm-bvp-camshaft-alignment.jpg?width=1400&name=09-hm-bvp-camshaft-alignment.jpg

Only other way is to remove the VVT/chain cover that the hpfp is mounted to. I doubt the tri-lobe is damaged if the CF is fine. Replace a CF when the black DLC begins wearing away form the contact surface to the tri-lobe.

[ROH ECHT]

Funny...I was thinking "why all the CF talk" and then I go on about it as well. 

OK, you have an excessive misfire in the #4 cylinder. Pxx300 is a general misfire code and is followed by xx301,302,303, 304...with the last number reflecting the cylinder. Typically you'll find this to be caused by a coil. Perhaps a damaged Spark Plug. Perhaps the injector has stopped working optimally. And worse, could be due to mechanical damage internally. You'll want to check compression in all four, but especially #4. If #4 compression is found to be low...valves or rings, even a busted piston has been found in these.

[rubdub]

Can you not see one peak with the hpfp removed? Even if you cannot, the area between the peaks may be grooved slightly if the peaks have been damaged in the past. If tuned with the hpfp upgrade, CF change is between 10k and 20k miles. Otherwise it should last much longer. The owner must determine CF life when "tuned/no hpfp upgrade" because rail pressure target will differ, as well as the driver habit to increase throttle position which requires more rail pressure. So, driving habits.

Another way is to remove the vacuum pump; https://blog.fcpeuro.com/hs-fs/hubfs/Images/Blog/active/Humble-Mechanic-Brake-Vacuum-Pump/09-hm-bvp-camshaft-alignment.jpg?width=1400&name=09-hm-bvp-camshaft-alignment.jpg

Only other way is to remove the VVT/chain cover that the hpfp is mounted to. I doubt the tri-lobe is damaged if the CF is fine. Replace a CF when the black DLC begins wearing away form the contact surface to the tri-lobe.

Thanks for the reply ROH ECHT! I could see the cam lobe and seemed to be minimal wear (if any, to my untrained eye) but I was hesitant of putting back the cam follower and pump with the cam being on a high spot. In Humble Mechanics video on it he says to rotate cam until it's on a flat spot, so that's why I was a but apprehensive of putting them back in. But after reading a few posts on the subject here, a few people were saying it's ok, but just to torque pump back on gently and with even pressure. So that's what I did, and happy days! 

[rubdub]

Funny...I was thinking "why all the CF talk" and then I go on about it as well. 

OK, you have an excessive misfire in the #4 cylinder. Pxx300 is a general misfire code and is followed by xx301,302,303, 304...with the last number reflecting the cylinder. Typically you'll find this to be caused by a coil. Perhaps a damaged Spark Plug. Perhaps the injector has stopped working optimally. And worse, could be due to mechanical damage internally. You'll want to check compression in all four, but especially #4. If #4 compression is found to be low...valves or rings, even a busted piston has been found in these.

Yep you're right it seems to have been the coil pack itself gone bad! Got a loan of an old one from a friend who upgraded to R8 coils a while back, and now seems to be running as usual again!

Cheers!