Need serious help from real experts !!

Hello I have a 2003 dodge neon sxt 2.0. I have had check engine light with

P0171 for a long time but never had any problem with my car. my problem

started 2 weeks ago with a no-start condition but after 30-40 minutes I could

start the car. So whenever engine is cold normally I can get it started but

once it warms up, I can't get it started or sometimes is sputtering very much

& the engine shuts down unless I floor gas pedal. Then I should wait for an

hour or try to start & start & start until it may or maynot works. Also once it

warms up, when I slow down on an stop sign or stop at a traffic light, the car

stops & I have to push it to a side & wait & try & try until it works. Also car

runs very bad & the acceleration is really bad. & Gas mileage is very bad too.

But the worst part is that sometimes when I drive, after I slow down, the car

stops accelerating & I have to floor the gas to force it to run about 3 Mile/Hr

!! it happenes most of the times but not everytime & I have to take the car

to a side & wait for an hour & pray that the next time I try to start, the

engine turns on & the car runs !


Autozone checked my battery, Starter & Alternator, all is ok. First mechanic shop told me it's from crankshaft sensor, the second one said it's camshaft sensor, I replaced both but nothing happened.

I changed the spark plugs & Fuel pump assembly but nothing happened. sometimes I have to wait an hour & start & start & start to be able to turn on the engine.

I already took it to 4 different "mechanic shop" but apparently they just called

themselves mechanic & they are just some "oil changers" !! Every mechanic

says something different, O2 Sensor, MAP sensor, Air leak, Coil pack, Fuel

pump, fuel filter, fuel pressure regulator & etc !!! I don't want to spend

another extra dollar unless I know for sure what is the problem. I am really

frostrated & pissed off. I really get tired of hearing stupid useless comments

from Non-Mechanics who call themselves mechanics. they tell me they cannot

figure out the problem unless it happens at the same time I am at their shop

!!! SERIOUSLY ?!? I still cannot believe that 4 different mechanic shop cannot

figure out a very simple issue with an 10-years old car !!! it's really shameful &

embarrassing !! I don't mean to offend anybody here but I have no idea how

government let these uneducated "oil changers" to rip innocent people off for

$100-120 per hour !!!

I am a student & I really cannot afford to waste any more dime for their
baseless random guesses.

However as I said before there's only one code P0171. now regarding this informations, If you are an expert & you believe on what you say, plz let me know what do you think would be the cause of problem :

1- O2 sensor
2- MAP sensor
3- Throttle position sensor
4- Coil pack
5- Fuel Injector sensor
or anything else ?!

Thank you very much for your time & your help