Please Help

[Nismo31]

Ok, I've had prolly the same problem for a good few weeks now. It has numerous symptons and it has been back and forth to the shop for that time period as well. I nor the mechanics can seem to tell wut it is. Hereit goes, it seems to sometimes have trouble starting. If i let the car sit for a day (8hrs or so) or more, she'll start up perfect like nothing is wrong. If i drive it for a lil while and then park and try to leave in a short amount of time, she wont start. Sometimes when i try and start she'll rev up and then die. in order to prevent this i have step on the gas and hold it for about 20 secs around 1k-1.5k on the tach. After doing that she'll run alrite during that duration. Another problem is the tach is outta wack. When i slow down to a stop sign, it'll go down to around 500k, almost like its gonna die and then if i remain stopped at a lite or like a stop sign, it will slowly rise to around 1.5k in a matter of 10 seconds. very weird. The shop said it was my TPS sensor. I changed that a 3 weeks ago but it seemed to do NOTHING. i dont have much car knowledge but it seems like the car is either not getting enuff fuel or it's getting too much air. it seems like a vacum leak or something. Also my gas mileage sucks a s s. It dont have many mods and i get around 12 mpg. I dont know why but i do. Well this is all that i can think of rite now. Thanks for your help.

-Rob

[NISTECH]

check your coolant temp sensors connector for corrosion to start. It is either that or idle air control cutting off the air to the engine to the point it chokes on fuel.