2000 Renault Megane car jerking while drive,like no power i

Start by adding a good fuel injector cleaner to the fuel tank to clean out the fuel system .. have the vehicle plugged into a diagnostic computer and please supply any fault codes !!

my mechanic cheangs 4 coil pack and map sensor he put on the computer and nothing come up on system now he is saying change crankshaft sensor please help me i do not know what i do i spent so much money but no luck.
please let me know what you think what shell i do

many thanks

hi, Check your engine breathers may be blocked with old thick oil ,blow out change your oil with correct oil , and change oil filter .
ps. before you do this remove oil filler cap and drive your car a short distance hopefully not two much mess if no problem its may be the eng/breathers,you have to use the correct oil (25/50) etc check with your supplier.

I would replace the CKP (crankshaft position) sensor and the spark plug wires !