Hyundai Tau (G8BA / G8BE)

Hyundai's V8 — 4.6 as the G8BA and 5.0 GDi as the G8BE — in the Genesis, Equus, Mohave and Kia's K900. An all-aluminium quad-cam design with variable valve timing, and the first Korean V8 built to compete with the Germans and the Japanese at that size.

Its long-term pattern is thinly documented, and volume is why rather than reliability. Very few were sold outside Korea and the United States, so the forums and bulletins that make an engine's faults legible barely exist. That is worth stating plainly rather than borrowing a fault list from a superficially similar V8, which is what almost everything written about it does.

What is established is ordinary for the type. The timing chains and their guides are the wear item on a quad-cam V8 of this age, announcing themselves as a rattle at start-up. The variable intake manifold's actuator sticks and costs low-end response without a dramatic symptom. And the 5.0 GDi is direct-injected where the 4.6 is not, so it accumulates intake-valve carbon at mileage and the 4.6 does not — the single most useful distinction between them for anyone diagnosing a rough idle.