The fact that it's happening with cold would tend to indicate a weak battery, however when you have a weak battery you'll usually get a click or a dimming out of the dash when you attempt to engage the starter. I would start with charging and load testing the battery (since it's easy and free), then check electrical connections at the starter.

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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.