after releasing accelerator, rpm stay high for 3-5 seconds and them come back to idle very slow. a mechanic told me that i should get butterfly serviced. i want to ask that can this problem fixed with using carb cleaner or wd40.
for example if i press padle at nautral to 3k rpm and release, it will come to 2k rpm and stay there for 3-5 seconds. then it comes back to idle slowly.
car is cuore 2005. mileage and starting is fine. problem is coming for few weeks.