please help

[getflushed]

hey guys!

new hear, thought i would try a different forum cuz i cant seem to get a good answer from my original forum, they r great help over there though!

so i have a 2000 maxima auto, with 140,000kms on it, so when i start my car in the morning, its really hard to start once i get it fired up ( i have a little trick to get it to start on the first try but will explain after) while i sit in my underground while it warms up if i give it a bit of gas to get it around 2000 rpm it will hang at 2000rpm and all by itself drop to 1800 for a brief second then to 1500 and hang there and you can hear the rpms pulsate a bit, i can push harder it wont move for the first little bit so i push harder, then boom it shoots up to like three grand. if i push the accelerator hard it revs normally its only when i feather it to 2000 rpm, the other related issue is if i dont let it fully warm up and drive off slowly, i can feel it hesitating, it feels simular to really warped rotors while accelerating and dissapears once its over 2000 rpm. i can still feel it when its warmed up but its not nearly as bad, i can feel it if im cruising around on flat surfaces at any speed lower than 70 kilometers in between 1500 to 2000 rpm, also when i take off from a red light i can feel kinda like a couple misses in the same rpm range. another thing which i think is related if im approaching a red light and it turns green befor i fully stop and i re apply the gas it hesitates big time between shifts. i dont know what it is but heres what ive done and maybe you guys can put me in the right derection

new pump and sock
new plenum gasket( checked for vac leaks and there is none)
tps tested ok
maf sensor was cleaned and tested but i dont know if the numbers are right for it i have them if you want me to post them
new plugs
new air filter
new coolant temp sensor
no missfires
fuel pressure is good
.....

so the trick to starting it perfectly is either i let it crank for 2 seconds knowing it wont start and try again right after it will fire right up, but to get it to start on the first try i have to turn the key to acc then start slowly turning it, and right befor it starts to kick the motor over i can hear my fp run let it re prime the motor and it will fire right up , even with starting it the wierd way i will still have the hesitation though, but at least it will start up on the first try!~

please help me guys!

[tigersharkdude]

Possibly the fuel pressure regulator. I say this because of your last few sentences. It sounds like your car is not getting the proper amount of fuel, and after pumping the gas it starts up.

From my experience the FPR is pretty notorious for going bad

[getflushed]

Yea but minus the starting issue I know a fpr would cause hesitation but I don't see it only affecting. Low rpm but maybe it could somehow. Ill look into it tomorrow thanks for the help!

Possibly the fuel pressure regulator. I say this because of your last few sentences. It sounds like your car is not getting the proper amount of fuel, and after pumping the gas it starts up.

From my experience the FPR is pretty notorious for going bad

[tigersharkdude]

my cousin had a starting issue just like yours, exactly the same way with having to pump the gas in the lower RPM range at start up. We changed the FPR and its never had a problem since

[getflushed]

Yea see, I don't have to pump the gas its either It will always start fine on the second try or I have to turn the key to acc then turn a little more so its just about to start cranking and I can hear the fuel pump run, I let it run for 2 seconds and it starts up. My idle is fine and high rpms are fine, its only having issues with starting up and then hesitation under 2000 rpm which is a lot worse when cold I'm assuming its worse when cold because the 02 sesors kick in and try and correct it, that's what makes me think its a sensor, but today after work I will check my fpr thanks guys! One question there is two fpr right one one each fuel rail?
, I had my fuel pressure checked but who knows!
k..... I'm stumped I can't figure this out and its driving me crazy