Failing pulley isn’t unheard of but you usually get a fair amount of warning for that.

 

The dpf life of about 150k Miles is normal I believe, but you can certainly get them off and cleaned for less than a new one.

Well, after many months, and lockdown, along with trying to find somebody who is really on top of these engines I finally have the car 100%! To update and close the whole saga I eventually found a real VAG Specialist Garage! The guys there really know the ins and out of all VAG vehicles and totally up to speed on the engines. First off they looked at the DPF being the problem, they initially used a chemical cleaning system they use on a regular basis which actually got the vehicle running, on it's own with all sensors and exhaust intact. However it would not run properly, so, they removed the sensor and put a camera down into the DPF and found that it had partially melted this being the main reason, along with the quick build up of soot which stopped the engine running. Result, 1 new DPF fitted, car ran better but lacked power with a loud 'induction' noise from the air filter. Quick run on the diagnostics showed "EGR Valve Excessive Flow", followed by a call to Skoda Technical who suspected the rear part of the system so new Low Pressure EGR Valve & Cooler fitted but still lacking in power and induction noise. They then replaced the EGR Valve at the intake manifold with little improvement so they left that on at no cost to me and decided to look further on the engine side. They removed the cam cover and found the real culprit of all the issues! 2 cylinders rockers on all 4 valves had snapped and therefore it was basically running on only 2 cylinders, even they were somewhat amazed the car ran as ii did with no miss fire, knocks or bangs. They came to the conclusion that the timing belt had slipped, pistons hit the valves and snapped the rockers. The original garage had replaced the timing belt, not very well apparently as there were 'tippex' markings meaning that no special tools to lock the camshaft were used and the belt had been over tightened. Top end was stripped, all genuine new parts were fitted along with oil and filter change now all is good. MOT passed, taxed and insured all set for another 100k+ hopefully?

I’m glad you’ve got it sorted, thanks for the update 

On 25/01/2021 at 22:50, ronnievincent said:

and the belt had been over tightened

Out of interest

Quick question - does the tensioner not select the correct tension itself, like the Fabia mk1? I have changed Fabia timing belt myself.  Does the Octavia 3 150 bhp TDI not have self tensioners?

 

Anyone changed the Octavia 3 150bhp 2l timing belt themselves (of course use the locking key!)