2002 Mazda Tribute, This is my 4th altanotar, and 3rd battery. It smells like rotten eggs. My headlights are dim and they flicker, sometimes windows wont roll down, and often my gauges jump.

The rotten egg smell would come from your catalytic converter. Your engine is most likely running too rich which makes the "cat" work too hard and give off that smell. Going through that many batteries and alternators shows that you have serious issues with the electrical system. I would do an amp draw with car running and everything that you can turn off off. Also check if the alternator seems very hot or if the battery is hot. One test you can do is to pull all the accessory fuses and one by one add them back in and note which one causes a larger than normal increase in amps. There could be other problems, but this is a good place to start.

Go to the Mazda dealer and purchase an alternator I just spend month and a half and 2 alternators trying to fix mine. Finally after buying a new battery and spending $345.00 the alternator works perfect it is reading 15.60 int he meter, all the electric system works great, even the air conditioning works better, the low voltage in the vehicle makes the lights dim and all of those problems, also check the power cable for the alternator I have to replace mine, it was rotten, that makes the alternator works bad. The Mazda alternators are expensive, but it is the right thing to do the voltage regulator is controlled by the computer of the vehicle.

it sounds like the ecu is malfunctioning,you can by pass by putting in a bridge rectifier and running it direct via a relay it wwould cost about £150 200 pounds

as for the cat try replacing the lambada sensor, and cleanining the air flow sensor your car will then tell the ecu to stop dumping fuel into the system where it is not needed.it sounds as if your car has not been serviced and maintained regulary regards j.s autos uk