Mopar 4854153AC Air Cleaner Body

Detach the cable from the negative terminal of the battery. Detach the flexible ambient air duct from the air filter box snorkel. Remove the wing nut from the cover and remove the cover and filter element. Inspect the element for contamination by dirt and moisture. Replace it if necessary. Clearly label, then detach, all hoses from the air filter box. Remove the air filter box assembly. Installation is the reverse of removal. Detach the cable from the negative battery terminal. Loosen the hose clamp at one end and remove the three attaching screws at the other end of the flexible air duct between the air filter box and the throttle body. Remove the duct. Clearly label, then detach, all vacuum hoses from the air filter box. Detach the heat riser tube from the air filter box. Remove the upper half of the air filter box lid, then remove the air filter element. Remove the two bolts and one nut from the floor of the air filter box. Remove the box. Installation is the reverse of removal.

The Air Filter Box (AFB) serves to provide heated intake air during engine warm-up and then maintains inlet air temperature within a 70-105 degrees F range by balancing warm and cool air intake, promoting leaner fuel/air mixtures for emission reduction and improved driveability. This balance is governed by intake manifold vacuum, regulated by a vacuum motor controlling a heat duct valve in the air filter box. During cold conditions, a shroud directs warm air from the exhaust manifold to the air filter box, aiding in quicker warm-up, while as internal temperatures rise, the vacuum-controlled heat duct valve gradually closes to draw air from a cold air duct. A time delay valve introduces approximately 100 seconds of delay before the complete closure of the heat duct valve. On certain models, a trap door mechanism similarly closes off outside air when the engine is inactive. To check its operation, ensure the engine is cold, inspect vacuum sources and hoses, observe the heat duct valve's position, start the engine to confirm it closes, and have an assistant operate the accelerator to verify valve movement. Reattach the flexible duct and check the valve's position after warming the engine. If issues arise, inspect linkages, vacuum hoses, and look for air leaks. If problems persist, direct intake manifold vacuum to the vacuum motor to diagnose further. For the bi-metal temperature sensor, remove vacuum hoses, cool it below 40 degrees F, apply vacuum, and observe the gauge. It should show vacuum at temperatures below 40 degrees F and none above 55 degrees F. Replace the sensor if faulty. To replace the heat duct valve vacuum motor, remove the air filter box, label and detach vacuum hoses, drill out the securing rivet, and remove the motor. Installation is the reverse, ensuring the rivet or screw doesn't obstruct the heat duct valve's movement. To replace the bi-metal temperature sensor, remove the air filter box, detach vacuum hoses, remove the sensor and its retaining clip, gasket, and note its position. Install the new sensor with a new gasket following the reverse procedure.