L24e Frustrations Help Please

[mr30_2.4e]

ok this is geting really frustrating.....

i got in the car thismorning (motor cold with temp senser connected) started idle well aprart from a slight misfirer racing a little cos it was cold then the idle came back to normal after a few moments. gave the engine a rev and it picked up nice and smooth. I then let it warm up to opperating temputure. Idle was still fine but as soon as i gave it a suden hit on the gas it coffs and spluters a bit and back fires out the throught the intake. Then i stoped the motor disconnected the water temp senser for the computer started the motor back up witch took more cranks then ussaul (usally starts straight up) once started had trouble keeping idel and amited a white/ grey smoke out the exorst. but seemed to rev alright and drove without hesitation...... i have tested my water temp senser with a multi meter and it seems to be working (got resistance/temp output from nissan manual) i replaced it anyway with another tested senser of my old skyline buy testing in diferent temp water but gave me same reading as the one in my car

??????????? anyone got any idears ?????????