advice

[fergusgorman]

hi guys.
My 350i is idleing fine but when accelerating engine will cough even missfire. Had been sitting for nearly three months with little fuel in it. Am wondering if sludge has been pulled through the fuel filter and starving it of fuel. Looking at tanks underneath car they are joined at a T piece then go into some sort of filter? From here they go into the fuel pump and afterwards into the fuel filter before off along the chassis to the fuel Pressure regulator Is this thecorect order. What is this filter lookalike after the T piece. Another filter? Both filters appear not to have been changed for a loooong time!

Thanks Guys.

[AM400]

The T piece is actually the swirl pot, there is a small guaze filter inside bit it is non cleanable, just to stop the big lumps of solder getting in from the tanks!

The other fuel filter is the one to replace, it should have a part number and date stamp on it, are you still using the old fuel?

Andy.

[350zwelgje]

fergusgorman said:

hi guys. My 350i is idleing fine but when accelerating engine will cough even missfire. Had been sitting for nearly three months with little fuel in it. Am wondering if sludge has been pulled through the fuel filter and starving it of fuel. Looking at tanks underneath car they are joined at a T piece then go into some sort of filter? From here they go into the fuel pump and afterwards into the fuel filter before off along the chassis to the fuel Pressure regulator Is this thecorect order. What is this filter lookalike after the T piece. Another filter? Both filters appear not to have been changed for a loooong time! Thanks Guys.

Does not sound like something is blocked to me.
I have to keep the tanks 25% full, otherwise the fuel circulating will cause that not enough fuel is available at the injectors for full acceleration. With nearly nothing in it, it becomes worse.
Did you fill it up to at least half full, and did it do the same?
Other options could be: electrical connections need cleaning, fuel filter needs replacing, or the fuel pump is on its way out.
Hope it is the first simple one.

For information, the fuel supply goes from the pump via filter to the fuel rail, and back via the pressure regulator.

Rob

[chris280]

I had a similar problem with my 280 when I first got it. It had been off the road for at least three years. Solved the problem by changing the fuel filter, which although it looked virtually brand new, was letting very little fuel through. Also drained out all the old fuel and replaced with fresh. I also find that I need to keep the tank above quarter full or I encounter pick up problems under load. I also ran some injector cleaner through the system on my first couple of full tanks of fuel. It has run fine since.