Nissans are famous for drive problems; suspect a partially engaging drive at the "off" differential.
its a Nissan for starters but it could be the plug wires or the plugs or the distributor
If they are vacuum operated then it could be the hubs.
A bad transmission gear can cause your 1999 Nissan frontier to shift hard. Low transmission fluid can also cause the transmission to shift hard.
The low pressure switch will do that when the system is low on freon.
On a 19 year old vehicle I would suspect you have a vacuum hose that is leaking. Replace all under hood vacuum hoses.
Front shocks. You may feel what I could describe as an "UP" bounce feel. If you replace the front shocks this will minimize that feel. However, the Frontier front suspension is quite "bouncy" good truck.
same thing started happening on my '97, you will probably need to have a new clutch cable installed. when they get old, sometimes they will start to fray which causes them to stretch and causes your pedal to become sticky.
it is happening in the Sahel region
When a bird walks or hops it moves forward
There is a magnetic float inside the washer fluid tank that causes a magnetic sensor on the outside of the tank to activate when the fluid is low. Either the sensor is bad or the float is stuck.
he he he
To prevent them from happening again.