Petrol Starting Problem

[mudabir.iqbal]

My baleno 2004 jxr now a days giving problem in starting at petrol. some times just 1/2 self, some times 2-3 long selfs followed by a lethargic start. and some times it takes 8-10 selfs and starts like coughing style and then rapid pressing of accelerators gives result. after start there is no problem in petrol running, no missing, under power, or any other abnormality.

Gas is fine all the time. if i direct start the car on gas its ok.
some mechanics say fuel pump is bad,... but i have check the pressure its good...fuel pressure is around 35-38 psi in engine bay.
some say pump is intermittent....
some say electrical problem...
i got the injectors cleaned....,fuel filter changed, spark plug and current tested. CNG and Petrol mixing tested.
scan through computer no error found

[pwuser165176643628]

@capsat

[sardarg]

fuel pressure is around 35-38 psi in engine bay.

sir the fuel pressure is low, it has to be above 50psi + at start when engine idles injector rail maintains the pressure and relieve excess fuel back to tank through purge valve. @ser_gtr @syncview @argtr65

fuel pump ko tanki sai nikal kar check karwa layn ho sakta hai fuel filter bag mai debris jo jis ki wajah sai fuel pressure low ho jata ho.

[syncview]

you need to do the fuel pressure drop test, to see how long it holds about 20psi after engine is switched off.
if it holds 20psi for about 5 mins and more, the system is ok otherwise you need to check lines for leaks and if all is well, replace the fuel pump.

[SER_GTR]

+1 Agreed

it could be your fpr or pump or some seal dropping it somewhere below avg

[mudabir.iqbal]

sorry for the late reply bro, thanks for your suggestion but meanwhile i changed the fuel pump and filter two months ago, and its works fine, the pressure at tank side is 40+ and in the engine bay its 35 to 38 psi.
car has no issues for two months but now as i mentioned it has starting issue on petrol but when i start the car on lpg and converted to petrol then no issue in driving at all , no missing no jerk.

[mudabir.iqbal]

thanks dear, its hold more than 35psi for 5 minutes.the issue is intermittent most of the time it wont start on petrol, but sometime on half sulf start, injector and injector rail are cleaned but with no effect