i changed the 2 thermostat sensors and it fixed the surging feeling and backfireing wtf...

can anyone explain this?

One way your ecu determines how much fuel to put in is by the coolant temp. When its cold your ecu dumps more fuel in the motor then when its warmer once reason is because if its cold the incoming air is more dense therefore requiring more fuel than less dense air so if your ecu thinks its cold all of the time you run very rich

Something like that IIRC

ohh i gotcha lol i was looking in the whole wrong dirrection for my problem i was looking along the fuleline/fule filter/crank sensor spark plug wires n all but its running great now