Hello friends, im a newbie here. my lancer sportback recently got jerking problem after routine service done at glenmarie mitsubishi service (change engine oil & spark plug @100k millage). First time i noticed the jerking i suspected it might relate to spark plug or its cable and second assumption could be my cvt gb. Its always happend whenever i start driving after stop (low rpm) and only several time occured at high speed. I sent back the car to them to troubleshoot, and they did troubleshooting connecting their laptops with my car and drive for awhile,then they suggest to change air filter which i think it nonsense at all. So i just change it with hopping that problem solve and as expected the problem is still happened. I called them and they ask me to send back to do troubleshooting again but now i dont want to waste my time sent back my car to them.

I need some advice from otai here or might be someone else have experice with this kind of problem, or could someone suggest me which service center or mitsu specialist workshop.

 

1. Check the torque on each sparkplug and gap.
2. Install four new spark plugs (it is not impossible to get a bad plug from the factory) (or if money is a real issue - buy only one new plug and swap until the problem goes away)...
3. Inspect the sparkplug/coil connection- they may have pulled one or more apart when disconnecting it from the plug...

But the MUTIII laptop should have revealed any one of these problems (see above). The only thing the laptop cannot detect is a failing or coked up injector. Try running Seafoam [tm] or any other good solvent through the gas tank...