Fuel filter replcaement?

Question

Hello all,
I am having a 1990,BMW 525i.Sometimes My Bimmer needs two or three cranks for starting.I have cleaned the fuel injectors with STP complete fuel cleaner and my sparkplugs are good.Do i need to change the fuel filter also?pls advice

Answer 1

A leaking fuel injector can cause this problem or a bad check valve in the fuel pump or faulty fuel pressure regulator. As fuel leaks pass the nozzle of a fuel injector it releases the static or holding pressure of the fuel system. Since the fuel pump relay is not energized until the computer "sees" ignition spark the engine has to be cranked first and then the fuel pump can then fill the system with fuel and pressurize the fuel. A leaking injector will also foul the spark plug or at least cause it to run rich. You will probably experiance rough idling after a long crank period if this is the case. A faulty pressure regulator or check valve in the fuel pump or external fuel leak will only cause long cranking times. A fuel pressure gauge installed between the fuel filtert and the injector rail will indicate wether or not the system is operating at nominal pressures. Shut the car off and observe the gauge it should hold pressure. If the pressure bleeds down you have a leak.

Answer 2

Oil filter should be changed with every oil change. The trouble sounds more like the alternator is acting up. Have the alternator checked.

Answer 3

i would its cheap and you can do it your self. just remember safety, relive fuel system pressure and disconnect the negative battery cable.

let me know if you run into any problems

Answer 4

it may not do anything but it wont hurt anything either, its pretty cheap to do if you use pep boys. autozone. etc. for an after market filter