It's not the engine. It's the #4 main cap bearing. The TDI, FSI, and TSI suffer the same incidents, but VW prefers to ignore the fix. Several bearing manufacturers have recognized the issue and made sets that compensate for the issue.
The issue is that the #3 piston/ rod assembly are the hottest because of the direction of water flow and usually the intake manifold aims almost directly into mostly, #3 cylinder, so it works harder and runs hotter.
The #3 rod is oiled by the #4 main bearing. The preemptive repair we do is to replace the lower solid #4 crank shaft main cap solid bearing with a slotted bearing of the same size and dimension. This changes the oiling of the #3 rod from a 50% duty cycle to 100% duty cycle. The oil galley that goes from the #4 crank main to the #3 rod is halted when the solid bearing literally shuts off oiling of #3 rod bearings for 1/2 of the rotation of the crank.
The most common incident arises from a warmer day (that probably didn't happen!) and a relatively long, fast drive in a heat-soaked engine up a nominal grade. All of a sudden, you have complete and catastrophic damage to the engine.
Many times, the cylinder head is intact. We had one person that drove a 3 cylinder engine for about 10 miles in that ruined condition. So, a block, at least the #3 rod and piston and maybe a crank, if bent and the engine can be recovered... we've done such a trick. Checking the cylinder head to see what's the chances, might leave you thinking the whole engine needs replaced.
As a matter of fact, we have posted many times of the entire replacement set of bearings we use which show two different versions of the same bearing made by Glyco; an 048 version and an 027 version. The 048 bearing set has 5 slotted and 5 solid bearings, with the solid normally going into the crank shaft caps. The 027 version has 4 solid and 6 slotted bearings with the 'extra' slotted going into the #4 bottom cap position. We used to get a lot of calls about the 'set that was made wrong.' and have been required to explain. Usually, we are replacing a single slotted bearing with the stretch bolts. It's a simple 'remove, check bearing condition, replace set if copper is showing', or just the single bearing and associated stretch bolts if just updating the bearing to eliminate a truly disastrous problem.
Sorry I come late to your crisis. Perhaps another 4 cylinder engine owner will not be so unfortunate. It is not what I call a common event, but when it happens to you, 'uncommon' really means nothing. Personally, I have only experienced maybe 10 and you would be only the second this year.
We sell a single bearing std shell for $8 and the two bolts I believe are $2.50 ea. Shipping to England is a bit prohibitive.
Hope you can recover from this incident. I'd be looking first to see if the timing belt is intact. Then, you could consider a short block. That is, with a modified #4 main bearing...
