Troubles with engine

[pedromvf]

Hello all,

I have a 2001 R1150R with 15000 miles and I went to a BMW dealer to service the bike. While driving the engine started working on an erratic manner. You would accelerate and there was no response, combustion seemed not to happen evenly and suddenly the problem would disappear. While idling on a red light the engine would stall. Once I touched the start button it would come alive again. The dealer thinks I should replace the fuel pump but according to a mechanic I know, the fuel pump is working fine and he thinks that I might have water on the tank. The engine has plenty of power and apart from this erratic behaviour that lasts for a few seconds every 5 minutes everything seems to be perfectly fine.

Have you had a similar problem or have any idea about it? Next week I am borrowing a tank from him to test if the problem is the pump or not. Anyway would be nice to hear about your experience.

Thanks a lot,

Pedro

[boxermania]

Pedro

Please nderstand that I'm trying to diagnose based on your post, with the bike site unseen. Just take these as things to eliminate in the quest for an answer.

I think the key here is the 5 minutes window of operation.....

If it is water, the bike would run rough and kill for as long as you had water in the tank....if it was lots of water the bike would kill and not start.

If it is the fuel pump, it would be making, most of the time, a noticeable screeching sound. You could also have a semi plugged fuel filter, but 15K mles is just too early.

I would have to guess that you might have a failing ignition coil, once it heats up it breaks down and cuts he spark.....or a Hall effect sensor.

That's what I can share with you....let us kow what you find.....

[pedromvf]

Thanks a lot for your insight boxermania,

Another reason for thinking it is water is that when I lean left the problem seems to get worse and last longer.

Does someone knows an easy way to empty completely the fuel tank? I will start cleaning the tank and suggest your ideas to my mechanic, see what he can do about it.

More ideas are welcome.

Cheers

Pedro

[CNorris]

I just went through a similiar thing, erratic running, sounds a lot like yours - thought it was bad gas but it wasn't. Tracked it down to an erratic left firing cylinder. Turned out to be the spark plug wires. My '02 has 48K on it. I'm not aware if there's a set service life for 'em or not. BMW spark plug wires are around $70 a piece (!).

[markg]

There is definitely a service life on spark plug wires. Very difficult to predict, but symptoms generally start out with very intermittant mis-fires.

[ProductUser]

If the problem didn't exist prior to taking it to the dealer, then it's possible that they mucked something up.

Do the easy part first: Try to remove as much gas as possible and put in some new fuel. Add some fuel additives that will dispurse the water, too.

ProductUser

[pedromvf]

Does someone know about any product to disperse the water in the fuel?

The misfiring started to happen when I was driving to the BMW garage and the bike was parked for without use for a while. I am running the bike as it is to empty the tank as much as possible, the idea is to dry it completely and refill it with new petrol.

Regarding the spark plug wires, I will check it although they look new and do not have any signal of wear and tear.

Thanks

Pedro

[Boxer]

Check and see if the right hand side throttle cable sheath is stuck up outside the adjuster ferrule. That's an easy one to miss and it causes all kinds of strange engine behaviors. It gets lifted up when the fuel QDs are pulled apart and rejoined by the mechanic to take off the gas tank.

[pedromvf]

Problem still there. Tomorrow I am going to the mechanic to borrow a new tank and pump all together. Once I try it I will post another message. Thanks to all that posted on this for now.

Cheers

[pedromvf]

Went to the mechanic on Friday afternoon and spend 2 hours testing the bike. First a new tank and the problem continued, then he tested a few items like spark plug cables, little injection box and a few other sensors. The problem is still there. At some point even the ABS system stoped working.

After reassembling the bike and waiting for a few minutes everything came back to normal except the engine that contuinues with the same symptoms. either stall if idling or the revs go up and down if you are holding the throttle at any point.
Don't know what else to do. in two weeks I will go back again and the mechanic will test the hall effect sensors and the fuel pressure sensor.

If someone has any other idea please post it here because I do not have any clue.

Cheers

[gel9001]

I would look into the Electronic Control Module or Motronic or whatever BMW calls it. I had a friend who's bike started with the same symptoms. A few months earlier he had opened up his engine managment box (which was rivited and not meant to be opened) so that he could install a "chip" to make his bike go faster. When he closed the box back up he didn't seal it with silicon as recomended. One day while riding in the rain, water apparently got in there and bike went haywire doing the kind of things you describe.

You mentioned bike sat a while, perphaps doing this time period humidity got into the "computer" and that is now causing your problems,
good luck,

g

[Ted]

Did you check your spark plugs against a chart like this?

Sounds a lot like my BMW 325i when I had a rather large but hard to find air leak in the intake bellows.

[Rockster1150]

A Cup of Methylated Spirits in the tank will solve the water issue, although I am one more to go with the previous electrical diagnosis'. Best of luck.

[HikerGlenn]

Oxygen sensor perhaps? It will sure cause a car to do some of the things you mentioned.

[pedromvf]

I have done 200 miles since the episodes started and I added a product to clean the tank and injection system and so far the problem improved. Now the reduction in revs is not that noticeable but it still happen. Apparently the tank had water or was dirty, not sure which one is the proper answer. The engine does not stall anymore which is good.

Thanks for all your posts guys.

Pedro

[boxermania]

Pedro,

Just for good measure I would do an idle and TB's sync.....as we don't know what is the current status of tune on the bike.

[bransan]

Pedro, use isopropyl alcohol to eliminate water in the gas. Use an injector cleaner for a few tanks of gas. Check the wire ties at the steering head for over tightened ties. I had 2 wire ties that were so tight they cut the wire. Intermittent problems can be difficult to diagnose, especially via the web. lol.