Stranded by fuel pump?

[ncsonderman]

On mile 200 of my Sunday ride, I lost power and had to coast to a (luckily) driveway and stop.

 

Running about 6K RPM in 4th gear, all of a sudden "BBBBBRRRRRrrrrrrrrr"

 

I dropped into third and tried to find power but none to be had. I was in a long consistent radius lefthander and needed to drop into neutral to coast to a stop.

 

I still read 2 bars on the fuel gauge...

 

Prior symptoms:

 

A couple of times earlier in the day, I'd experience a hiccup that I attributed to being the rev limiter. Upon further reflection though...

 

I did notice what seemed to be surging a couple of times today as well as during my commuting around town the last week. (My bike normally doesn't surge noticeably)

 

History:

 

It's a 97 R1100 RT with 16,800 that I picked up last August with 10K on the clock. I just got back from a trip to FL with no problems.

 

I dialed Chris Kinney for some tech support and we changed out fuse #6 with no result. Next swapped out the relays also with no result.

 

The Rider Information Display works fine when the ignition is turned to the on position as does the ABS sensor. Missing is the whir of the fuel pump initialization.

 

I was able to rely on a good friend, his infant daughter and his father to drive about 65 miles to Lawsonville, NC to pick me up. A big dinner through down is definately coming their way

 

Anyone had this happen before (of course it has, I just had to ask )

 

Where do I go from after I strip the tupperware?

Thanks,

 

Joe

[Steve W.]

May be the dreaded HES failure. Take a look at this link, explains it all in detail.

http://advwisdom.hogranch.com/Wisdom/oilhead_hall_sensors.pdf

 

Happy Hunting

Steve

[Bprimm]

I think you need to look for a connection that came loose.

 

The fact that you do not hear the initial whir of the fuel pump upon turning the key to "on" doesn't automatically mean the Hall sensor is the culprit.

 

Has any work been done that might lead you to check the fuel pump connector at the tank...that is has the tank been off for fuel filter change or anything?

 

The mileage you have on the bike leads me away from Hall sensor failure.

[ncsonderman]

No MXS that required tank removal or anything with the fuel pump.

 

About the Hall Sensor, I thought that you were to look for the RID failure during troubleshooting to point you in that direction.

 

[ShovelStrokeEd]

Nope, Hall sensor won't effect the RID.

 

The lack of the initial whir from the fuel pump is significant though. Turn key off, turn key on and fuel pump should run for 2 seconds and then stop providing all the other interlocks are satisfied.

 

First the easy stuff, is the RID normal? That would eliminate both the side stand switch and the kill switch as culprits. Does the neutral light come on?

 

Could be a fuel pump failure, do you know if the fuel filter was ever changed?

 

Once the tupperware is off, you can raise the rear of the tank and access the fuel pump and fuel level sensor connector. I'm out of town just now so can't give you wire colors to check but, someone will. Check that the power is arriving at the connector with it unhooked from the tank. As I said above, it should energize for 2 seconds when you turn the key on. If it doesn't, the problem may not be the pump but something electrical upstream. If it does, go buy a new pump and filter and plan on removing the tank and digging around in there to get the plate off.

 

Given the age of your bike, I have seen some nasty stuff up in there. Fuel screen completely rotted away and what remains full of crap. Fuel filter so clogged that it is impossible to blow 50 PSI of air through it. Check with Beemer Boneyard. I think they have a whole plate or two for sale.

[Bprimm]

quote]About the Hall Sensor, I thought that you were to look for the RID failure during troubleshooting to point you in that direction.

 

Not RID failure...more like the RPM display jumping in confusion while you are trying to start the engine. [

[smiller]

The fact that you do not hear the initial whir of the fuel pump upon turning the key to "on" doesn't automatically mean the Hall sensor is the culprit.

In fact it means that the Hall sensor isn't the culprit since it is not involved in the initial 2-second fuel pump run, that function is programmed into the Motronic. Assuming that your RID works when you turn the key on, check all of the electrical connections in the path to the fuel pump. You could also short across the appropriate terminals in the fuel pump relay socket to see if you can force the pump to run, whether that works or not should help narrow it down. FWIW failure of the fuel pump itself isn't very common, usually such problems are somewhere in the wiring.

[Bprimm]

 

Quote:

The fact that you do not hear the initial whir of the fuel pump upon turning the key to "on" doesn't automatically mean the Hall sensor is the culprit.

In fact it means that the Hall sensor almost certainly isn't the culprit since it is not involved in the initial 2-second fuel pump run

 

Very good Seth. You are absolutely correct.

[Stan Walker]

You have eliminated the easy things, kill switch, sidestand switch (you did say the RID was working), fuse, and the relay. What is left would be easiest to troubleshoot using a volt meter.

 

Do you have one, and are you confortable using it?

 

Stan

[Stan Walker]

By the way, which relays did you swap? And did you put them back?

 

Swapping a bad fuel pump relay with the motronic relay will produce a similar set of problems. Swaping with the horn relay is better.

 

Stan

[Stan Walker]

The first thing I would check is that F6 has 12V on both sides.

 

The second thing would be the signal that goes from the relay to the fuel pump. It's a green wire with a white stripe going to pin 2 of the connector that feeds into the fuel access plate on the right side of the fuel tank. The same signal can more easily be checked at the green wire with white stripe on either of the fuel injectors. Of course you must turn on the ignition for this, the sidestand must be up, and the kill switch in the run position.

 

I hope this is enouth to get you started. Keep us posted.

 

Stan

[Jerry Johnston]

Make sure the gas filter is ok.

[ncsonderman]

RID was fine and neutral light comes on. I did replace the relay with the horn and sidestand kill switch relays with no result.

 

I've got a multimeter that I'll break out before the game tomorrow night.

 

Since I was out an extra few hours, I had to go grocery shopping and catch a movie with the wife before I was allowed to play with my toys again

 

Update forthcoming!

 

Go Buckeyes

[Bill Dennes]

This happened to me once on a K-bike. I was sure it was the fuel pump. A BMW rider named Jerry Beem stopped to help me, and saved my bacon. (This had happened to HIM before.)

 

It was the fuel filter. If the filter is blocked, the pump won't pump. Jerry had a spare filter at his home nearby and got me on the road within an hour.

 

[ncsonderman]

 

I plan on taking care of a bunch of things while I'm down there. I'm going to install some quick disconnects (probably Jiffy-Tites if they call back with a price), adjust/replace my choke cable, change the fuel filter, and make sure all of the connections are solid.

 

Since I'm taking my tank off, I'm probably going to go ahead and perform my annual brake MXS and install bleeder valves up front.

 

Sometimes it takes something like this to "make" me lay up for a while and get some things done.

 

Thanks for the thought and I'm glad you had a better experience on the side of the road than I did. Thank goodness for good samaritans!

[timboaz]

Had something similar happen to me on my 96RT not long ago. Dealer had it for weeks- tried fuel filter, fuel pump, computer, plugs and on and on- ended up being the rubber fuel line in the tank. It got old and cracked and prevented good fule flow. Very inexpensive to replace, but very hard to diagnose.

[Ken H.]

but very hard to diagnose

Not if he had put a fuel pressure gauge on the bike early on like he should have done.

[ncsonderman]

Well I finally got the time to make some jumpers and tested my fuel pump. I really wasn't anticipating the amount and distance that the fuel pump sprayed. I guess that is a good thing since I know that it is functioning. Next is to see if I can staple up the screen filter. If not replace it.

 

I've already swapped the fuel filter and checked the hoses for blockage. I've got the fuel injector clamps on the hoses for next time as well.

 

The quick disconnects are now on the fuel lines.

 

I guess it's time to take the lap top into the garage and check some wires. I'll check the ones you suggested first Stan.

 

Do I check these with the igniton on?

[Stan Walker]

Do I check these with the igniton on?

 

Yes. Keep in mind the fuel pump only runs for a few seconds each time you turn the ignition on.

 

Stan

[ncsonderman]

Replaced the gauze filter for the fuel pump. Also needed to replace the vibration damper since it was dry rotted. Got everything back together now and turned the ignition on...

 

I now hear the fuel pump initializing. I tried starting the bike and got a few coughs as it was actually trying to start. This is an improvement as before it would just turnover and not give me anything.

 

I hooked up the battery tender to charge the battery as I think that the charge was a little too low after sitting for the last month+ .

 

I'm crossing my fingers for a positive result when I get back from a few errands.

 

[ncsonderman]

Has anyone ever tried one of the diagnostic tools that are available for around $40 on Ebay?

 

I was just thinking that may shorten my troubleshooting if they work.

[ncsonderman]

 

I'm here with another rider troubleshooting the now electrical problem.

 

Using our meter, we are checking voltage on the F6. 12.4V was measured on the back side of the fuse socket, but we could not read any voltage on the front side of the fuse socket.

 

Is the front the red and green wire that runs to the fuel pump relay or the red wire that runs to the ignition and the battery?

 

If I'm going to have to take it to the shop, I'd like to tell them what to look for.

 

Thanks.

[Stan Walker]

Using our meter, we are checking voltage on the F6. 12.4V was measured on the back side of the fuse socket, but we could not read any voltage on the front side of the fuse socket.

 

Assuming the fulse was installed, you should always read the same voltage on both sides of the fuse holder. If not, you have either a bad fuse, or a bad fuse holder. I would replace the fuse, even if you think it looks ok.

 

Is the front the red and green wire that runs to the fuel pump relay or the red wire that runs to the ignition and the battery?

 

I have no easy way to tell, other than by looking with a flashlight (you can do that). The diagrams don't show location. I would guess the red wire since it comes directly from the plus side of the battery.

 

Stan

[ncsonderman]

 

We took the reading without the fuse in. The fuse read continuity accross the tabs.

 

I looked at the wires and really couldn't tell where the wires went to although it did look like the red and green wire went to the front of the fuse socket.

 

I'm going to let Carolina BMW plug in their Bosch tool and tell me whats wrong starting on Thursday .

 

I'm struggling with this problem but really would prefer to be riding.

 

I'm riding a HD Ultra Classic this week and got to ride around a DR650 Suzuki last weekend so I'm getting my fix in the meantime

 

Thanks for all of your help in trying to get this worked out! Bottom line is I've got to have it ready for the BMWRA International rally in Asheville next month.