Good day lovely people of this beautiful forum.
Pls I need una assistance with my car. It all started that whenever I start driving the car for the first 20-30mins if I don't rev the car high to like above 3000 the car will be jerking gently kind of, and if I check the rev meter too it will see the needle going up and down small small, but after driving for a while it will stop and the car will move very well. Since this is not a major issue I kept using it that way till I will have time to visit the mech not until few days ago that while I was going back him in the night the car stops accelerating, like I press the throttle but it will not respond all I am hearing is a clicking sound under the carpet of the seat beside the driver in front. Once i press acceleration the and car want to respond I will just hear the click sound and the car will not respond to me again, then I off the engine and light then start it again this time the acceleration just respond a little above the 1000 rev on the meter then the car start to move small small till I got home that night. The following morning the car drives like nothing happened to it the previous night but I took it to my mech who said I should go and scan it, which I did and the person said something that one wire has cut somewhere or something and he fix it the check engine light on the dashboard went off and the car temp meter that doesn't work before start to work. Also the fan start to work in auto mode because before when I on the engine the fan will start immediately, but now the fan might not start for the first 30mins of driving and when it start it will be working in low speed (don't know if it is normal ) though no overheating .
Now the problem is I am not sure what he fix is what is affecting the gear problem and the issues I face the other night while going home. And I don't want it to happen like that again before I fix the issue permanently which is why I want to seek the opinion of car gurus on this platform. Thanks in anticipation for your input.

The car is nissan sunny 2011

ANYBODY