Intermittent problems are the worst. I had a coolant leak that took months to locate because it only leaked once in a while. Turned out it was a loose hose clamp.

That dealer story does sound a bit odd, but as long as it's under warranty and a loaner is provided, they can mess about all they want.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.