OD stuck off, tachometer is 3-4, guzzling gas, is my transmission going?
So basically your tranny is not shifting? Could be stuck shift solenoids. Check the tranny fluid, you may just need a fluid flush and filter change. Could also be clutch pack or torque converter. Solenoids are around $30-40, sometimes it's cheaper to just DIY replace them than to take it to a tranny shop which more often than not try to sell you a bill of goods you don't need.
03 mazda the transmission is computer controlled so you should at least pull the codes and see where that leads you, it may very well be shift solenoids as almost every car manufacture is having shift solenoid problems when you get a little mileage on them.
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