My car's idle is very rough. After startup, the idle is up and down, and dead if not gear up. If quickly gear up to anyone, it runs fine. Occasionally it can happen during your driving, but if you add some gas, it will be fine. The car runs fine, especially in highway, but the milage was not good, only about 15 mile in local, 24 in highway. I though it was a old car, this is OK. But the idle is too rough, I worried it is getting worse, and stall some day in my driving. I am thinking change O2 sensor and clean mass airflow sensor/ idle spped mtor after reading this forum. Can these be done myself? I am completely layman about car, just have Hayes and Clinton manuals. And also, what else can I do? Thank you in advance.
Yes, you can easily do all of those yourself. Though before you replace a component that may or may not be bad, does the vehicle's check engine light come or flash? If so, then the computer is setting a code that can give you a clue as to what's wrong.