Limp mode is a safety feature in modern vehicles that limits the power output of the engine when certain sensors detect an issue. When limp mode is triggered, it can cause poor performance and decreased fuel economy. Common sensors that can cause limp mode include the mass air flow sensor, camshaft position sensor, crankshaft position sensor, throttle position sensor and oxygen (O2) sensors. The mass air flow (MAF) sensor measures incoming air and reports this information to your vehicle’s computer. If the MAF fails or becomes clogged with debris, it will send incorrect data to your car’s computer which can trigger limp mode. Similarly, if either of the two camshaft or crankshaft position sensors fail they will also send inaccurate information to your vehicle's computer triggering limp mode as well as other issues such as misfiring cylinders or stalling under load conditions. The throttle position (TP) sensor monitors throttle opening angle in relation to engine speed and sends this information back to your car's PCM for proper engine operation; if it becomes faulty you may experience reduced responsiveness from pressing on the accelerator pedal due to limp mode being activated by its failure . Finally, O2 Sensors measure how much unburned oxygen is present in exhaust gases so that feedback control systems within an internal combustion engines can adjust accordingly – if these become faulty then there could be too much fuel entering into the system leading to excessive emissions resulting in a limped-down state until repairs are completed.