Volkswagen W8
4.0 L · W8 · naturally aspirated · petrol · 2001–present
Also known as: w8, 4.0 w8, passat w8
Volkswagen's 4.0 W8 — in the Passat B5.5, and nowhere else.
⚑ It is two VR6-style narrow-angle fours on a common crankshaft, at 72 degrees to each other — which is what makes a W rather than a V, and why an eight-cylinder engine fits transversely in a family saloon.
That packaging is the whole difficulty. Eight cylinders, four camshafts, two balance shafts and a great deal of plumbing occupy a bay designed for a four, and almost every job requires the front of the car removed. A quote made from any other engine will be wrong.
Its known items are the balance-shaft chain tensioners and the secondary air system, both of which fail with age and both of which are behind that packaging.
Roughly 11,000 were built, which puts parts and specialist knowledge somewhere between scarce and personal. The W12 in the Phaeton and Bentley uses the same idea at a different scale.
Cars fitted with this engine
1 generation, across 1 make. From the authored catalogue — an absent car means the catalogue has not reached it, not that the engine was never fitted.
Volkswagen
Information, not instruction
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- The car — make, model, year and engine. The same fault behaves differently on each.
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