s 350 suspension gone down no pump noise
Look for a blown fuse or tripped suspension switch. Read thru your owners manual about ride control as well.
Right rear corner of engine compartment fuse box, one of the maxi-fuses is for the air-matic compressor. If its blown, your compressor is probably junk. If the fuse is good, try disconnecting/re-connecting the main battery in the trunk. Start the engine and try the switch again.
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