|
Replacing the Fuel filter is the first step. If this problem continues after fuel filter replacment then this is signs of the fuel pump starting to go.
The best way to determine this is get a fuel pressure guage and hook it up to the fuel injection fuel rail take a reading. There is a fitting somewhere on the fuel rail that you hook the guage to. The fuel regulator trys to maintain anwhere between 35-50psi. I would double check this spec with the dealer to see if you can narrow this range further. Check the pressure at idel and then check several times while reving the engine. If the fuel pump is on its way out you will get readings in the 5-15 psi range.
The problem here is that sometimes the fuel pump does not "die suddenly". It may read in the normal range at times and then it may dip below the normal range (say 15-20 psi). In this case the computer trys to compensate and keep the injectors open longer. At times it may go in the (5-15psi) range. This is when it won't start or has a hard time starting. To prevent from being stranded when this happends you can try turning the ignition off and then turning in the ON postion for 5 seconds without starting the car. After 5 seconds turn the igniton off and then "on" again for anothe 5 seconds.
Do this about 10-20 times before trying to start the car. Everytime you do this, the computer activates the pump for a few seconds before stopping it when the computer detects the engine wasn't started. Turning the ignition on and off like this about 20 times forces a weak fuel pump to build pressure in the fuel rail. With good luck the car will start after 20 times of cycling the ignition as mentioned above.
Another way of diagosing fuel pump weakness is to borrow the diagonsing computer from Murrays. Not the the simple code scanner you need the real-time code scanner.
Hook it up to your diagnosing port under your dash and you can read your sensors in real-time as the engine is running.
the Only values you are interested in looking at are the "Fuel Trim %" for Bank 1 and Bank 2.
Although this sounds very technical it is not. The Fuel Trim is the computer telling you how much in percent it has to modify the fuel-mixture to keep the motor running. This perecent could either negative or positive. If I remember right a negative number means the computer is compensating by RICHENING the mixture and positve is Leaning.
There is a Fuel Trim % for Bank 1 and Bank 2. Bank 1 the cylinders on one side of the motor and BANK 2 are the 4 cylinders on the other side.
When you watch the fuel trim for both banksyou will see your car's computer will be within + or - 10% at all times. This is normal. If you see your computer going higher say + or - 20% for both banks then it the computer is trying very hard to compensate and there is a problem when it is compensating this much.
The computer will ALWAYS try to compensate by richening the mixture when there is a weak fuel pump. I don't remember if the richening produces a negative or positve Fuel Trim Value. I believe this would be a high negative perecantage.
I Hope this helps.
|