->''"No one but me can keep this heap running."''
-->-- '''Nancy Callahan''', from the ''Comicbook/SinCity'' story "That Yellow Bastard."

Sometimes the owner or driver of a vehicle has [[MachineEmpathy a certain connection]] to their vehicle (be it a car or spaceship etc.) and a way to demonstrate that bond is to make the operator the only individual who can make it run. In the hands of someone else it will fail to start or come to a stop after a few seconds without the gentle touch of the person who knows the special trick to starting the engine or all the little adjustments you have to make.

It tends to happen with either the very best or very worst of cars. TheAllegedCar is so rotten through that it needs someone with great knowledge of all its faults to keep it going (and sometimes overlaps with PercussiveMaintenance when only the owner knows the sweet spot). The AceCustom CoolCar can also be full of complex gadgets that you need to keep track of. Or maybe it's just so cool it only deserves the really attentive owner.

Because [[AutomatonHorses horses are just another kind of vehicle]], a MoodyMount may respond this way to a FluffyTamer (compare OnlyTheChosenMayRide).

When TheHero has a car which stands out for its dated design, it is the HerosClassicCar.

Related are EmpathicWeapon and LoyalPhlebotinum, which typically will ''only'' work for the owner. (Though it is not unknown for a character using this trope to talk as if that trope was in play -- the difference is that those tropes are for devices that ''refuse'' to work for anyone else while this one is for devices that ''malfunction'' without the owner's special touch.) A BlackBox is when the "I" in the equation is not present, and the people involved try to bulldoze their way into forcing the something to run, with unpredictable results. MagicPoweredPseudoScience is when the maker is the [[AWizardDidIt wizard who did it.]]



[[folder: Anime & Manga]]
* Eureka of ''Anime/EurekaSeven'' is [[spoiler:at first]] the only one who can pilot the Nirvash [=TypeZERO=].
* Simon is the only one who can pilot the [[Anime/TengenToppaGurrenLagann Lagann]].
** This seems to have more to do with the fact that he's the only one with a [[CoolKey core drill]], not counting [[spoiler:Lord Genome]], and they might not be interchangeable anyway.
** In addition to the key, the Lagann is attuned to Simon because of his latent Spiral power. Other characters develop Spiral power over time, [[spoiler: and eventually get their own Lagann-type mechs in the end]], so it's likely that someone else could pilot it if Simon gave them the core drill. The one time he tries, Kamina rebuffs him because he recognizes that Simon is better suited to it.
* Kaneda's bike in ''Manga/{{Akira}}'' is tricked up enough that he's the only one who can keep it going. When Tetsuo tries to steal it, it ends up winding down and landing him in trouble.
* Hayato from ''Anime/FutureGPXCyberFormula'' is the only person who can drive Asurada, since the car has an AI system with a unique security feature.
* Explained as one of the problems with the [[Anime/MobileSuitZetaGundam Zeta Gundam]] by the time ''Anime/MobileSuitGundamZZ'' rolls around. By the end of its service life, the Zeta Gundam was so customized and tailored to Kamille Bidan's specs that while Judau and later Roux are able to pilot it with some effort, they can only as much as it's base specs allow. They can't access the biosensor to let it do the crazy things Kamille made it do in Zeta because only his mind could trigger it, even though Judau was an even stronger Newtype than Kamille and later on ''can'' make use of his own Double Zeta Gundam's biosensor.
** In ''Anime/MobileSuitGundamSeed'', Kira is initially the only person on the Alliance's side able to pilot a mobile suit because, as a Coordinator, he has much greater multitasking abilities than a normal human, and mobile suits are too complex to operate without those. Later, Kira is told to place a lock on the Strike's systems that only he can open when they dock at an Alliance base. The reason for this is that the Alliance is [[FantasticRacism heavily racist against Coordinators]], and having that lock there gives Kira a bargaining chip to protect himself.
** In ''Manga/MobileSuitGundamSEEDAstray'', the OS of the Red Frame Astray is tailored so that only it can use the Gerbera Straight katana without blowing every servo and gear in a Mobile Suit's arm.
** ''Anime/MobileSuitGundamUnicorn'': The Unicorn Gundam has been hard-coded with a DNA scanner set to Banagher Links, meaning he is the only person that can pilot it, which is the primary reason the various factions keep him around rather than just stealing the Gundam for themselves.
** ''Anime/GundamReconguistaInG'': The G-Self only responds to three people: Raraiya Monday, Aida Surugan, and Bellri Zenam. Which is odd, considering that Aida and Bellri had never seen the suit before. Anyone else who sits in the cockpit and presses buttons gets completely ignored. It turns out that [[spoiler:it had been coded by its builders to only respond to Raraiya as a security measure for her mission to Earth... but had also been programmed to accept commands from the members of the Rayhunton family, which both Aida and Bellri are, though they didn't know it at the time.]]
* In ''Anime/GaoGaiGar'', the titular mecha could only be piloted by Guy. Originally, anyway.
** It's likely any G stone powered being could use it. It's just that Guy was one of only two around and the other was kid that was too young to use it properly. Gaofaigar on the other hand was fueled by his Evoluder powers which were unique to him (Mikoto's were different) which meant only he could use it.
* In ''Anime/CodeGeass'', Lelouch's second season mecha the Shinkirou features a scattering energy cannon and the strongest BeehiveBarrier in existence. However, it takes an exceptionally smart and quick-thinking pilot in order to draw out their full potential; in the hands of anyone but Lelouch, it's still high tech but not nearly as powerful.
** It's also mentioned that Suzaku is the only person capable of making the Lancelot ''move'', let alone do anything else. Same with Kallen and the Guren SEITEN.
* In ''LightNovel/FullMetalPanic'', Sōsuke is the first person to pilot the Arbalest, an experimental Arm Slave loaded with black box technology, and is later forced to become its designated pilot since the mech's quirky AI (named Al, with an "L") became calibrated to him and can't be reset because its creator committed suicide. This causes problems in ''The Second Raid'', since Al's eccentric nature (among other things) starts wearing on Sōsuke. It's later mentioned that Al simply won't ''let'' anyone else pilot the Arbalest; when Mithril tried, Al kept asking "Where's Sergeant Sagara?" and then shut down and refused to start back up when told that he wasn't around.

[[folder: Comic Books]]
* Archie in Franchise/ArchieComics sometimes plays this trope straight, sometimes pokes fun at it. For instance, in one comic, Arch said he couldn't lend the car out to Betty because he was the only one who knew how to keep her running. Oh course, when the car ''did'' break down and he couldn't figure out what the problem was, [[WrenchWench guess who figures out how to fix the jalopy...]]
* Nancy Callahan of the ''ComicBook/SinCity'' story "That Yellow Bastard" has a car so old and in such bad shape that it will stall out on anybody who tries to drive it, except for her. When her kidnapper, the title character, can't get it working, he has to take her to the Roarks' infamous farm on foot, giving Hartigan time to catch up to them and save her.
* In ''ComicBook/SuicideSquad'', Briscoe claimed to be the only one capable of piloting the team's helicopter Sheba. Given how possessive he was about Sheba, and that she seemed to respond to the sound of his voice, no one was ever quite game enough to test his claim.
* DependingOnTheWriter, the Batmobile sometimes has anti-theft features specifically designed so that no one except Franchise/{{Batman}} can start it. An interesting incident happened during the tail end of ''[[ComicBook/{{Knightfall}} Knights End]]'': after [=AzBats=] drops into the river, Batman races to the Batmobile (which somehow followed them) and tries to get in. Jean-Paul changed the locks, but Bruce overrode them. He hops in, starts it up... and the Batmobile ''[[MadeOfExplodium explodes]]''. He survives and tells the Tim Drake Robin that he would have done the same thing for an anti-theft deterrent, but not like ''that''.

[[folder:Film-Live Action]]
* Biff in ''Film/BackToTheFuturePartII'' had a very sweet ride which only he could start the ignition of (to the bemusement of his mechanic). After the {{Exposition}} of this in the scene with the mechanic, it's used as a sort of time travel TrustPassword by his future self who had come to give him [[TimelineAlteringMacGuffin Gray's Sports Almanac]].
** It's also notable that the [=DeLorean=]'s starter motor never stalls out for Doc, only for Marty.
* In ''Film/TwoThousandTwelve'', the car that's used to escape from the plane would only start from Yuri's voice recognition.
* ''Film/TheTransporter'' has his cars equipped with a keypad that requires a correct code to turn the key. The second film starts with a bunch of punks trying to steal his car only to find out that it won't start without the code. And Frank won't give them the code. Then they make the mistake of trying to [[TooDumbToLive beat it out of him]].
* In ''Film/MadMaxFuryRoad'', the [[BigBadassRig War Rig]] driven by Imperator Furiosa can only be driven after activating a convoluted sequence of switches under the dash. Which the titular character found out, much to his chagrin.

* This is kind of the point of ''Literature/AtlasShrugged''.
* When [[spoiler:Mr Gilbreth]] dies at the end of Literature/CheaperByTheDozen the family sells the car for scraps, seeing how he was the only one able to start it.
* In ''Corner of a Round Planet'' this is subverted, but not averted. All Auggies have a custom-built rig that responds to their particular brainwaves. The rigs lose significant efficacy when the wrong driver attempts to use them.
* In [[Franchise/StarWarsExpandedUniverse Shadows of the Empire]], the ''Millennium Falcon'' is described as this, with Han Solo and Chewbacca having over-customized the freighter to the point where even Lando (who had heavily customized it himself before ownership changed hands) can't do proper maintenance on it because the circuitry is such a mess. Interestingly, it fits ''both'' sides of the trope; it's [[TheAllegedCar The Alleged Spaceship]] to [[WhatAPieceOfJunk look at it]], but [[AceCustom one of the best ships in the galaxy]] with Han Solo flying it.
* Rangers' horses in ''Literature/RangersApprentice'' can only be ridden if rider asks for permission in specific words mounting for the first time. Anyone who didn't gets a free lesson in doing somersaults.
* Creator/JamesHerriot, after much badgering of his boss Siegfried Farnon, was finally granted a car to do his vet rounds in. What he ''got'' was a vehicle that was a potentially dangerous risk even by the standards of the free-and-easy 1930's. [[note]]Long before Great Britain introduced those pesky laws about maintenance, insurance and even having to pass a driving test before getting out on the road. Nanny State, eh?[[/note]] Herriot soon got used to driving a car with no floor under the driver's feet and some distinctly underpowered brakes, which almost had to be manually pushed up hills. But the local garage mechanic almost crashed it while reversing it into the working bay, noting, with typical Yorkshire understatement, that
-->Your brakes aren't ower-savage, vitnary.''
** He got an upgrade after Siegfried borrowed and crashed it, demanding to know afterwards who'd bought such a junkyard on wheels.
-->well.... you did, Siegfried.

[[folder: Live Action TV]]
* ''Series/KnightRider'': Michael Knight gave the explanation that the car's on-board computer could read his fingerprints - it's more plausible than the car having AI.
* Implied in the old ''Series/DoctorWho'' episode "The Pyramids of Mars" that only The Doctor can operate his TARDIS. He may have been lying, though...
** TheMaster sure had no trouble using it, though it may be that only a Time Lord can use it and the Doc is ''usually'' the only one around.
** Steven and Leela have both managed to pilot it.
** So has River Song - though it's been both denied and implied (in that order) that the Doctor taught her to drive it.
*** Ultimately denied: she was taught by the TARDIS itself.
** In the 2010 Christmas special ''A Christmas Carol''; this time it's not the TARDIS in question but, a device that will save the lives of people aboard an out-of-control shuttle craft in a cloud belt storm. Although it's not a vehicle, it's a machine that controls a planet's clouds. Too bad the only one who can work the controls is a bitter old sod who couldn't give two dumps about what happens to the people aboard. The Doctor gets so fed up with the man's heartless personality that he goes back in time to directly alter that man's past so he doesn't grow up into such a monster. Unfortunately, the Doctor's meddling works ''too'' well and [[spoiler: the machine no longer recognizes the man because his personality has become remarkably different.]]
* A partial example occurs in ''Series/{{Lexx}}'': Only one person has the "key" to the titular ship (a small EnergyBeing that embeds itself on the recipient's hand) at any given time and it can only be passed on by the original holder dying or being "brought to the height of sexual ecstasy". Severing the owner's hand seems to work too.
* Played for laughs on an episode of ''Series/{{Cheers}}''. The gang takes a road trip in Cliff's car and crash. Getting the car back on the road requires some things Cliff didn't tell them.
-->'''Sam''':Cliff, I'm turning the key, but nothing's happening.
-->'''Cliff''':That's because I've got it rigged up with a Cliff Clavin Anti-Theft System. What I do is I turn the wheel all the way to the left.
-->(Sam turns the wheel.)
-->'''Sam''':Got it.
-->'''Cliff''':And then I turn the key as hard as I can.
-->(Sam turns the key.)
-->'''Sam''':Oh dear. Cliff, I just broke off the key in the ignition.
-->'''Cliff''':I said as hard as ''I'' can, Sammy!
* ''Franchise/{{Stargate|Verse}}'': A lot of Ancient technology was programmed to only respond to their DNA. As it happens, they interbred some with ancient humans, so a few modern humans have the particular gene the technology is programmed to respond to, and can activate it. Similarly, the Goa'uld programmed much of their tech to only respond to themselves, this time based on detecting naquadah in the blood, which only Goa'uld (and their hosts) will possess. However, someone who was once a host to a Goa'uld will retain that naquadah, so the tech will still accept them despite the absence of an actual Goa'uld.

[[folder: Tabletop Games]]
* The [[OurOrksAreDifferent Orks]] of ''TabletopGame/{{Warhammer 40000}}'' have a latent psychic field that allows their vehicles to function in bizarre ways because [[ClapYourHandsIfYouBelieve they believe they can]] ([[FunetikAksent Red wunz go fasta]], planes keep flying until the pilot is informed they ran out of fuel a while ago, etc). So when a non-Ork uses one, it tends not to work. DependingOnTheWriter, this may be [[DownplayedTrope downplayed]] or [[ExaggeratedTrope exaggerated]]:
** Sometimes this is presented as total ItRunsOnNonsensoleum, such as a Codex entry where some Imperial techpriests opened up a gun they had actually seen an Ork fire and found it was an empty shell full of a few broken parts and some ''loose'' bullets rattling around at the bottom.
** Elsewhere it's presented as Orks actually having an inbuilt propensity to build primitive but genuinely workable technology, and the psychic effect just smoothing things out a bit. For example, Literature/CiaphasCain ('''HERO OF THE IMPERIUM!''') at one point had a sizeable fleet of commandeered ork vehicles for his ragtag refugee army. The techpriest he had along was fascinated by them, as they ''seemingly'' shouldn't have worked at all, but most still did work with neither her help nor that of a nearby Ork.
* In ''TabletopGame/{{Pathfinder}}'', the gunslinger class starts off with a basic gun which only they can use properly, and can therefore only be resold for scrap. This is something of an ObviousRulePatch, since firearms are among the most expensive non-magical items -- the ones available as starting weapons should cost 1000 to 2000gp; more money than they should see for at least a couple of levels. Without this rule, it would be a choice between [[EarlyGameHell making 1st-level gunslingers go barehanded]] until they can afford a starting weapon, or allowing them to [[VendorTrash sell it the moment the game starts]] for far more money than they should rightfully have access to.

[[folder: Video Games]]
* Quite a far out example, but in ''VideoGame/BreathOfFireII'', your town can be turned into a FloatingContinent that can only be controlled by your father, who has been wired into the technology.
* In ''Franchise/MassEffect'', Joker says something along these lines when asked about piloting the Normandy.
** Played very literally in the time between the second and third game. Joker and EDI (the second Normandy's AI) collude to give the impression that EDI is only a Virtual Intelligence that will respond only to Joker.
* In ''VideoGame/JadeEmpire'', Kang says the same for the [[GlobalAirship Marvelous Dragonfly.]]
** Both of those expand the trope from just being about clunkers in the hands of someone used to their quirks, to extremely sophisticated devices in the hands of a specialist.
*** And in Kang's case he spends literally every hour of the day making modifications to the Dragonfly (he doesn't sleep). The controls probably change completely from flight to flight.
* The Alteisen from ''VideoGame/SuperRobotWarsOriginalGeneration'' is an impractical junk heap of a HumongousMecha that's very hard to handle due to its grossly encumbered frame, unbalanced weight, and ridiculous amount of thrust. Only Kyosuke is stated to be able to handle the machine within the story, thanks to his devil's luck. [[GameplayAndStorySegregation However, in gameplay, there's nothing that's stopping you from switching in any other pilot.]]
** The thing about the Alt, and it's upgrade, is that piloting it is much like gambling. To use it effectively, the pilot has to dash in and hammer the enemy with close-to-mid-range weapons. The pilot can do a lot of damage this way, but it also leaves them wide open enemy retaliation; It's a high-risk-high-reward style of fighting. Kyosuke, being TheGambler, likes to fight that way, and has the skill to pull it off.
** The heroes of ''VideoGame/SuperRobotWarsAdvance'' also has this going, as Axel Almer and Lamia Loveless hail from the Shadow-Mirror universe, and they're pretty much the last remnants of the organization, and none of them are science types, it is impossible to reverse-engineer their mechas, so pretty much only Axel can pilot the Soulgain, and only Lamia can pilot the Angelg, and meanwhile, only both of them can pilot the Vysaga. The rest will have to content with the available-for-mass-production ones like Ash Saber and Laz Angriff (in fact, the latter one became the default mech of Yuuki Jaggar). This is not a problem because not only Axel and Lamia are pretty much excellent pilots, those three robots pack serious punches in whatever it is they do (brawling, sniping and sword-fighting)
** In the mainstream series, on one hand, it's justified with certain pilots always driving certain robot as it would be illogical to let pilots from different series do. On the other hand, real robots such as Gundam usually plays with this. While UC and [[Anime/TurnAGundam Black History]] pilots are interchangeable, unique Gundam series such as ''Wing'', ''X'', and ''Seed'' are stuck with their respective mechs.
* The third ''VideoGame/DynastyWarriorsGundam'' combines this with MythologyGag. Any Mobile Suit with AttackDrones, [[PsychicPowers psycommu systems]], or is otherwise confirmed to require superhuman or extrasensory abilities to pilot can only be selected by pilots with the Newtype attribute[[labelnote:*]]For the sake of conciseness, this tag also encompasses [[Anime/MobileSuitGundamSEED Coordinators]], [[Anime/MobileSuitGundam00 Innovators]], [[Anime/TurnAGundam Moonrace]] et. al.[[/labelnote]], even when the license to unlock it for everyone other than its signature pilot is obtained.
* In the original ''[[VideoGame/RatchetAndClank2002 Ratchet & Clank]]'', only Clank can start Ratchet's ship at the beginning of the game, since Ratchet is missing crucial components that makes it start. This aspect is almost immediately forgotten, until Clank reminds us of this after the first boss fight.
* [[spoiler: Licia]] from ''VideoGame/DarkSoulsII'' says this about a certain rotating door. of course, [[spoiler: she's lying her heart out. Should you killed Licia via Crushed Eye Orb invasion, you can obtain her miracle and the Rotunda Lockstone. In this case, only ''you'' can make the door go]]. Ultimately, this trope is played straight no matter what circumstances.
* The Last Hydral in ''VideoGame/TheLastFederation'' is the only one who can control Hydral technology. Occasionally you'll find a battlefield where another race has managed to switch something on, but it's always berserk and attacking indiscriminately.

[[folder: Web Video]]
* Mr. Regular of ''WebVideo/RegularCarReviews'' occasionally encounters a decidedly ''irregular'' car that requires special care and attention to operate properly. Footage of the owner explaining its quirks to him so he can actually drive it is often left in the main video, unedited, instead of being relegated to the usual POV video that goes up a few days later. Some notable examples:
** The Dodge Aspen, which is a shoddily built car that has aged poorly and has trouble turning over.
** The Ford Model T, which is one of the oldest cars in the world and was designed before people really knew what they were doing -- the owner spends ''over three minutes'' trying to explain everything.

[[folder: Western Animation]]
* A large part of the premise of ''WesternAnimation/MegasXLR'' is that Coop messed around with the mech's interfaces while refurbishing it, to the point that Kiva can no longer make heads or tails of it. Therefore he has to pilot it. The modified interface consists of a [[CoolCar Plymouth Barracuda]], [[IKnowMortalKombat several different game controllers]], and many, many {{Plot Sensitive Button}}s. Even Coop has trouble with it.
* In an episode of the ''WesternAnimation/TheFlintstones'' where Fred gets himself fired, Mr. Slate is forced to get him back after discovering that his handling of his dino-crane has made it so that only he can use it properly. Which makes sense since it's an animal--that he tamed.

[[folder:Real Life]]
* Certain high-end cars, such as Mercedes, tried this particularly those sold in countries prone to carjacking, sometimes offer thumbprint recognition as an ignition lock. Unfortunately, this just makes carjackers [[{{Fingore}} cut the driver's thumb off]]. Some thumbprint recognition devices also make sure the thumb is alive first (i.e. check for temperature and blood flow).
** Additionally, [[DrivingStick manual gearboxes are not as common in the United States as they were previously. Which makes for excellent theft deterrence]].
* In The Netherlands in September 2014, a monster truck accidentally drove into the audience. The police tried to reenact the tragedy, but [[http://www.rtlnieuws.nl/nieuws/binnenland/nasleep-ongeluk-monstertruck#node_1144201 was unable to get the truck started.]] According to the lawyer of the driver, it takes "a manual of two A4-sized pages" just to start the vehicle.
* Many highly modified and custom built cars require specialist knowledge usually only possessed by the owner to be driven without blowing something up or in some cases just to start the engine. Most highly tuned cars will have an array of additional gauges on the dashboard displaying everything from boost and oil pressures to air fuel ratios, if these go too high or too low then a mechanical failure is more or less guarenteed. vehicles with race ignitions will often require a series of switches to be flipped in a certain order rather than just turning a key.
* On the other end of the spectrum, horrible jalopies often have chronic malfunctions, all of which are known only to their owners. If the carjacker does not know that one has to (for example) clean all spark plugs with sandpaper before starting the engine, he won't start it.
* In a non-automotive example, some televisions can be like this. If a person is used to the setup of one system, using someone else's can result in a lot of trial and error to watch something. Factor in DVD players or video game systems and things get further complicated.
** This can expand even further with one gamer's PC to another. Differences in PC configurations and peripherals can cause players to lose games against players with significantly inferior skills.
* Electronic devices can commonly fall into this. On the one hand, you have power users who [[AceCustom customize everything they own]], often removing things they don't need/use, altering settings in sometimes arcane ways, changing keybindings, and many other things that will make it a nightmare to use for anyone but them (sometimes this is done intentionally). On the other hand, you have generally incompetent users who [[TheAllegedCar perform no maintenance]] and exert little or no control over the device, making it difficult for even an expert user to undo the mess without a complete system reset. At the extreme ends, you have devices so heavily customized that even the original user forgets much of how to use it after an extended period away from it, and devices so mucked up by clueless owners that it's simpler to format them to solve whatever problems they have.