Engine Problem Help [long]

[philabeemer]

Folks,

Bought an '04 dual-spark R1150R about a year ago. The bike sees heavy use as a daily commuter and I have already clocked up 17,000 miles. The problem I am having started a couple of months ago when the bike started surging at low speeds/low RPMs, such as those I frequently encounter on the highway commute. As most pre-dual spark owners appear to already know, by surging I mean the it was the same kind of sensation you get when you are about to run out of gas - feels like the engine is not getting enough fuel.

Took it into the dealer who synch'ed the throttle bodies and did a valve adjustment and replaced an apparently filthy fuel filter (which was supposed to last 20,000 miles). The bike ran just fine for a week . . . then the surging came back.

This time it was accompanied by surging a full-throttle acceleration in 3rd/4th/5th/6th gears. Took it back again and this time they discovered a faulty oxygen sensor, which they replaced.

Naturally, the problem reoccurred the day after I picked it up and was on a 1,000 mile weekend. Took it back, and this time they found a "piece of black plastic" in one of the fuel lines just behind the fuel injector. They replaced both injectors as a precaution and, of course, took out the plastic bit, which they thought might have been dropped in the tank during manufacture.

The bike ran fine for a week - again. Then the problem came back. This time I am getting surging when I am maintaining a steady speed in 3rd or higher gears and holding the engine at over 5,000 RPM. I am about to take it back yet again.

I think my dealer is great, and has gone over and above to try and figure out what the heck is going on with this bike, but would love to hear some opinions from anyone on the forum who might have encountered similar problems. I think the poor dealer is pretty much stymied at this point, and is calling BMW for help.

I love this bike, and would really like to get this issue fixed!

Thanks,
Mark:dunno

[ghostrider1]

i'll gander a guess that somehow, somewhere you picked upa load of crap in some fuel and the piece they found in the one fuel line has a family following it,

saw a car once with a piec of rust partially blocking the fuel pump intake, would idle fine but ran like crap under load...

of course i could also be full of it too.. so just a thought

c.l.

[BMWRich58]

Took it back, and this time they found a "piece of black plastic" in one of the fuel lines just behind the fuel injector.

These are just my thoughts......

If you've ever seen and changed a fuel filter in the tank, you would have noticed a rectanglular shaped meshy white/almond colored thing on the pickup side of the fuel pump. That is what most people call a "fuel sock". The mesh is very very fine. It's job is to filterout the much larger pieces junk before entering the fuel pump. (So how big was this piece of plastic???)
Then the fuel goes through the pump and onto the regular fuel filter before entering the fuel lines and to the injector. So what your saying is this piece of "plastic" made it past "two very fine filtering devices"(first the fuel sock and then the fuel filter). Well apparently then these filters have " large holes in them" or the fuel is being picked up some other way and "by- passing" these "fine meshed filters"....:dunno

I picked up a bad load of gas in Jackpot Nevada in the summer of 2002, and after repeated filter changing, I finally arrived home to where I could wash the fuel tank and lines out completely. I also had the injectors professionally cleaned at a place that cleans fuel injectors for cars, trucks etc. The guy said that "yes they were dirty"(checked spray pattern) and got them cleaned. Injectors either work, get clogged(dirty) or don't work. "No such thing as a lazy injector".

My fuel tank cleaning, disclosed all kinds of crap in the tank.
Bits of fuel pump sock I believe from the station that I fueled up at and where all the problems began, fine shiney metal dust particles,bits of clear plastic maybe from a syphon hose I used for stealing gas for the lawn mower,and a greyish black dust.
The latter maybe being from the charcoal canister after a totally
"up to the top" fuel fill.
The black dust also appeared to have collected on the backside of the fuel injector, and when tapping the fuel injector upside down on a white paper towel, the dust particles came out.