MAF

Have the Engine Computer's stored diagnostic fault codes read first. They will get you to the right circuit or system with the problem. Many auto parts stores will do that for you for free. If you have a code for the mass air flow sensor, you can try cleaning it first, but wait for a few hours after you stop the engine. Some of them go through a self-cleaning cycle after the engine is stopped. They get real hot to do that and cleaning chemicals will shatter the sensing element if it is sprayed on at that time. If cleaning doesn't help, the sensor can be replaced. Also be sure there are no leaks in the tube between the sensor and the engine.

Can be replaced but not repaired. If problem is intermittent, check for loose or contaminated wire connectors, that would be the most likely cause.