The usual cause is the dog (gear) on the end does not move out fast enough due to dust/dirt build up.
A clean and lubricate with dry silicon lube will sort that issue out.
Disconnect the battery, disconnect the power cable on the rear of the starter motor.
Unbolt and remove the staer motor, clean lubricate NOT WITH OIL! that will make it attract more dust and reassemble.
Question edited for clarity.
Question move to model category.
It looks like you will have to buy a service manual
https://www.google.com/search?q=Ford+StreetKa.+Wiring+diagram
Sometimes you can find part diagrams if you search
(year) Ford Ka (the part) wiring diagram
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Question edited for clarity and add maker.
Question moved to model category.
Don't swap out parts based on guesses.
Take spark plug 4 and put it on cylinder 1, put 1 in 4. Does the misfire move to 1? You need a new plug.
Or an auto electrician can diagnose the misfire with a 5 grand scan tool computer in about 30 minutes.
https://www.google.com/search?q=mobile+auto+electrician+near+me
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Too many possibilities and limited information. Does the engine still run and the car does not move? Or is the engine not running so that the car stopped? Repost the question with additional information.
check your transmission fluid level while vehicle is "off " it should be higher than normal . Now Check the fluid a 2nd time with the vehicle running if the fluid has not moved fromits original mark like from the first you checked it your torque converter may have worned down splines but your fluid level can lead you in the right direction.
Connect a battery charger to it. Get under the front of the engine and put the positive lead on the big red starter wire and the negative on a clean bolt on the engine. Within an hour, there will be enough charge to get in and open the hood and fully charge the battery.
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Our automotive electrician Jeff posted up at the top. Better down here. You also have good information from Kardoc, you have a dead short to ground.
Jeff Armer Dec 26, 2023
How can I get wipers and blower to work???? You can't if you don't know how to test automotive electrical circuits, using wiring diagrams an diagnostic trouble charts from factory service info.
www.alldatadiy.com
The engine produces combustion and moves the pistons. The rotational motion of the pistons is transmitted to the transmission then converted into the energy to drive the wheels. The electric motor's power source is a battery pack. The energy goes through the regulator and then to the motor that turns the wheels.
Being a Ford, check the ground (-ve) battery cable to both engine block and frame/bodywork.
If the ECU detects a 'fault' it may unlock the boot and possibly the doors, thinking an emergency has arrisen.
If you cannot change the gears when the engine is not running, then you probably have an internal transmission problem. Could be input shaft or cluster gear assembly
