Q: Engine start to tremble when pressing gas. One time the engine light started flashing.

Hi Stephan. Thanks for taking time to contact us today in regards to your Nissan Altima’s issues. Anytime the engine or warning light illuminates, it’s due to an error code being created by one of the multiple fuel, ignition or drive-line sensors on your vehicle. The codes can be downloaded by a professional mechanic during a check engine light inspection, which provide them with a starting point to begin the diagnosis process. Generally speaking, the type of symptoms you are describing are caused by fuel system component failure, ranging from a mass air flow sensor that is damaged or dirty, EGR valve, clogged fuel injectors or a dirty throttle body. Worn out spark plugs and wires can also cause this issue. You might want to have a professional mechanic come to your location and complete an onsite inspection, so they can correctly identify the root problem and recommend the right repairs.