Where is the speed sensor - 1999 Mercury Sable

Does your versa have automatic transmission or CVT transaxle Makes a difference

Lorraine, speed sensors are not located on engines. there are transmission speed sensors and wheel speed sensors.
Check the attached links,instruction and guides, Good luck
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Speed sensors locations Google Search

Vehicle Speed Sensor Location

vehicle speed sensor VSS

wheel speed sensors Google Search

Hi Nicholas, Im AL the owner of Big As Auto Repair.

FRONT WHEEL SPEED SENSOR

REMOVE

1. Raise vehicle on jack stands or centered on a frame contact type hoist. See Hoisting in the Lubrication and Maintenance section of this manual, for the required lifting procedure to be used for this vehicle.
2. Remove the tire and wheel assembly from the vehicle.
3. Remove the speed sensor cable routing bracket Speed Sensor Cable Routing Brackets from the steering knuckle. Remove the wiring harness sealing grommet retainer and speed sensor routing bracket from the inner fender.
4. Remove speed sensor sealing grommet from the inner fender Wheel Speed Sensor Connection To Vehicle Wiring Harness Then unplug the speed sensor cable from the vehicle wiring harness Wheel Speed Sensor Connection To Vehicle Wiring Harness
5. Remove bolt Speed Sensor Head Attachment To Steering Knuckle attaching the speed sensor head to the steering knuckle. Then remove speed sensor head from steering knuckle. CAUTION: If speed sensor head locating pin has seized to the steering knuckle, do not attempt to remove speed sensor head by grasping with pliers and turning. This will damage the speed sensor head. Use only the following procedure.
   
6. If speed sensor head can not be removed from steering knuckle by hand, the locating pin on the speed sensor head has seized to the steering knuckle do to corrosion. Remove speed sensor head from steering knuckle using the following procedure. Remove disc brake caliper from steering knuckle, and remove brake rotor from hub/bearing assembly. Then insert a pin punch through hole in front steering knuckle Speed Sensor Head Removal From Steering Knuckle and tap speed sensor head locating pin out of steering knuckle.

Hope this helps and please visit my auto-repair-website at:
http://www.bigasautorepair.com/

there several speed sensors 1 on every wheel for abs called wheel speed sensor and in transfer case 4wd or awd call output shaft speed sensor or vehicle speed sensor and input shaft speed sensor which can be a computer generated signal from crankshaft sensor and output shaft speed sensor this is to determine torque converter lock up.

the output speed sensor is located on the transmission. while standing in front of the vehicle and looking down at the transmission you will see two rubber hoses. under those hoses you will see the input speed sensor. if you look to the right of that sensor, and you may have to look from underneath the vehicle you will see another sensor that is identical to the input speed sensor. That is the output speed sensor. The output speed sensor is the one that shows how fast you are moving on the speedometer.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

SECTION 206-09: Vehicle Dynamic Systems 2006 Explorer/Mountaineer Workshop Manual REMOVAL AND INSTALLATION Procedure revision date: 11/03/2007 Wheel Speed Sensor Ring - Rear Printable View (134 KB)
Special Tool(s) Installer, Wheel Speed Sensor Ring
206-084/1 Installer, Wheel Speed Sensor Ring
206-084/2

Item Part Number Description 1 2C182 Wheel speed sensor ring 2 4K138 Halfshaft Removal

1. Remove the rear halfshaft. For additional information, refer to Section 205-05.

1. Using a suitable driver, remove the ABS wheel speed sensor ring.

Installation

1. Install the new ABS wheel speed sensor and the Wheel Speed Sensor Ring Installers on the halfshaft as shown.

1. Using the Wheel Speed Sensor Ring Installers, install the ABS wheel speed sensor ring as shown.

That depends on WHICH speed sensor you want to change. The Vehicle speed sensor? a front wheel speed sensor? A rear wheel speed sensor? an input shaft or turbine speed sensor?

There are four speed sensors
Compressor speed sensor
Transmission speed sensor
Vehicle speed sensor
Wheel speed sensor

Yes, I would start at the speed sensor on the transmission called the VSS (Vehicle Speed Sensor).

Also, are the tires the right size for the vehicle as indicated by the placard on the inside of the door?

The following is the example for some GMC Envoys (I had to guess on the engine size):

Vehicle Speed Sensor Removal & Installation To Remove:

1. Disconnect the vehicle speed sensor connector. Vehicle speed sensor (A), Retaining bolt (B), O-ring (C)
   
   
2. Detach the vehicle speed sensor from the transfer case.
3. Remove the o-ring from the vehicle speed sensor.

To Install:

1. Apply transmission fluid to the o-ring.
2. Install the o-ring onto the vehicle speed sensor.
3. Attach the vehicle speed sensor to the transfer case. Torque the bolt to 97 in-lb (11 Nm).
4. Connect the vehicle speed sensor connector.

hi , their is two different speed sensors on your vehicle one is the input speed sensor which is inside the transmission and the transmission will have to be removed to replace it the other one s the output speed sensor is located directly above the passenger side trans-axle shaft. your input sensor is the sensor which tells the transmission when to shift and the output speed sensor tells the speedometer what it should display and both those parts are fairly cheap they are around 15-25 dollars but just remember if your input speed sensor is bad it is gonna cost you a minimum of 1000 dollars to have a mechanic fix as the transmission needs to be removed hope this is what you needed