Po 507

1997 chevy cavalier 2.4 lt engine auto, fast idle going up and down, replace the sensor and the problem persist, new plugs, new cables, new coils, new ignaiter, new housing, and the problem remain, if you run the AC and get to a stop the car just died.

P0507 code for this car I would suggest the Fuel Pressure Regulator (FPR) I had the same code and this seemed to help with that problem. BUT have you checked vaccum lines first especially the map sensor vaccum

Well you said FPR. Where is located, and how do i checked. I went to advance auto and PO 507 is hight idle, i rep;aced the IAC idle air controler and the problem remain, the idle goes hight and low and the car run really bad.:evillol:

it is a 70.00 dollar part @ AZ and it is located at the end of fuel rail , the one with the vaccum line running to it you have to pull the fuel rail out and roll it over and it is then easier to work on. release fuel pressure slowly.I am not a hundred per cent this will cure you ill's but I did have same code and this code is not specific to a certain part. so it could be something else but this did take care of mine. you will need torx bit to work on.10 mm socket short and long. YOU could also get some TB cleaner and wash out those injectors and some new injector o-rings while your there....use a little oil on the o- rings to reseat. it is not a hard job

Well no vacum leaks, and the map sensor was replaced, ant the problem still desame, i'm going to replace the FPR and i hope this will cure the problem.:banghead:

Finally i get to fix the problem was a vacum leak from the intake manifold, so we replaced the gasket and the car is runing fine now.:evillol: :evillol: :evillol: :evillol: