That code would make me tend to think the sensor was bad out of the box (It happens.) or there's a problem with the wiring.

As for checking the throttle linkage, remove the air filter and whatever else you need to see the throttle butterfly, then floor the pedal while a helper looks to see if it goes fully open.

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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.