Help! My 1998 R1100R has no spark
 

I purchased my first BMW bike about 8 months ago. It's a 1998 R1100R 75 year anniversary edition with ABS brakes. About 38,000 miles. Great ride, but I have had one problem after another with it so far. My latest issue is that the bike died on me all of a sudden after I parked it and I had to have it towed back home. There is no spark. Following are all the things I have checked or fixed so far:

1. Checked kill switch (working)
2. Checked clutch sensor (not working, but when I connected the two wires in the plug, did not resolve issue with spark
3. Kick start sensor (Working)
4. Checked the fuses (all good visually)

I checked and there is power running to the ignition coil, but no power coming through the coil.

4. Checked the resistance on the ignition coil (Primary wingding resistance 0.5 ohms and secondary winding resistance 7.5 ohms) Bought a used ignition coil since the Haynes Service manual says that the secondary winding should be 13 k-ohms for the 1100 series, but exactly same readings. Turns out that BMW later model ignition coils are 7.5 k-ohms for secondary winding. Oh well, at least I have a spear.

5. Decided to take out the dreaded Hall-sensor and sure enough the wires are completely bare and falling apart. Bought a new Hall Sensor, installed and still no dice. At this point I am starting to lose my mind.

6. Ran a temporary ground from battery's negative ground to the frame to test that it was properly grounded and still nothing.

7. Disconnected the battery for 30 min to reset the computer and still no dice.

The interesting thing is that when I test the plug running into the ignition coil from the harness, one of the two wires is always live. Is this normal or should it only come on when I try to start the bike? My brother suggested testing to see if it comes on intermittently when I crank the bike, since the hall sensor should be triggering the charge intermittently, but it does not. The light on my voltage tester flickers just from the draw down from the battery when I press the start button, but never turns all the way off.

Any suggestions at this point would be greatly appreciated. I love working on bikes, but I love riding them much more. Having this beautiful mike just sitting is a sad sight :( Could it be relay issue or the motronic control unit? Thank you again for your time and advice.

Allan

Hi Karringaa :

Sounds like you measured the coil. I believe you said one of the two wires to the primary was live - I think that's sounds good, you must have found the hot wire. The other wire out of the primary goes to the Motronics ( ECU ) and will provide the ground ( when triggered by the Hall sensor ) to fire the spark plugs.

The coil secondary circuit forms a complete path. From the one side of the secondary , down to one spark plug, to ground , up from ground on the other spark plug and back to the other side of the coil secondary.

The Hall sensor not only triggers the coil but also the fuel injection.

When you first turn on the bike do you hear the fuel pump prime ?
When you hit the starter button, are the fuel injectors emitting fuel ?

Both spark plugs will fire at the time.
Both fuel injectors will fire at the same time.

I think you're saying it turns over but there is no spark. If so, the sidestand switch, and neutral switch (or clutch switch) are working. It won't turn over if you don't have the sidestand switch + clutch or neutral switch.

Have you checked for spark by pulling a plug and grounding it against the frame? If not, I'm still suspicious of your HES. Was it raining before you had this problem? IF so that's a good indication of a HES issue. I'm told you can check the HES by turning the engine by hand with the key on. It should fire the fuel pump every 180 degrees. I've never done it myself.

Measure that you have +12 V on Pin 30 of the fuel pump relay and also Pin 30 of the Motronic relay. Replace their respective fuses if you don't--fuse 6 for the fuel pump and fuse 5 for the Motronic.

Make yourself two jumper wires with spade terminals. Remove the Motronic Relay and the fuel pump relay and place jumpers between pins 30 & 87 in each relay socket. The fuel pump should run continuously and you should get a spark.

Let us know what happens.

(Note: If your relays are marked differently and have pins labeled 3 & 5, then pin 3 should have +12 and the jumpers should go between pins 3 & 5.)

[QUOTE=JimMoore;8963365 I'm told you can check the HES by turning the engine by hand with the key on. It should fire the fuel pump every 180 degrees. I've never done it myself.[/QUOTE]

This is a good tip - has anyone tried and can confirm if this works? I'd try, but my bike is in pieces for some maintenance.

Yes, I have used this to check timing and the fuel pump.

Thank you for your response. I do hear the pump when I turn the bike on.
This is my first bike with fuel injectors, so I am not sure how to check if the fuel injectors are emitting fuel. Also I turned the engine over manually while the key is on and could hear the pump turn on every 180 degrees.

Yes I pulled the plug and tested it against the frame. (No spark) It was not raining before I had this problem. Completely dry and just died after I parked and came back from the store.

I turned the engine over manually as you suggested and can hear the pump turn on every 180 degrees. Should the pump be turning on exactly as I see the TDC mark in the viewing window, because it's not. Making me a little nervous that I did the timing wrong when I put the HES and timing belt back on. Thank you for your time.

Yes, the pump is turning on every 180 degrees. Should the pump be turning on exactly as TDC is seen in the viewing window or is the pump not exactly timed with the piston being in TDC.

Just want to make sure I did my HES/timing belt change correctly. Thank you.

I will definetly give this a try as soon as I get a minute and will post an update. thank you

Looks like the HES is working.

The HES triggers the fuel pump, fuel injectors and spark.

Looks like the fuel pump is working.

You can check to see if fuel is being injected by :
a. Smell exhaust.
b. Pull spark plug and smell.
c. Pull fuel injector and watch it spray fuel.
It's the device that's fitted on top of the intake manifold ( throttle body ) with a
fuel connector and an electrical connector.
The fuel injector is held on by 2 allen bolts and a couple of clips.

How far off is it? I wouldn't worry about a degree or two.

You did check for spark?

My terminals are numbered 1-5. Fuel pump works fine, but no spark. It's has to be the ignition coil. The last replacement i got was used and k-ohms on secondary terminals was around 7.5 for both ignition coils that I have. It think they are both burned out. Just ordered a brand new one and hopefully that will do the trick. I will update once I get there.

About 5-10 degrees, give or take. The OT is not visible in the window by the time pump goes on.

I did follow the instructions in the manual when replacing the HES. Placed motor at OT mark in the middle of the viewer and placed home made stopper pin in the flywheel hole. Then moved the HES until the signal for the sensor just turned off. Tightened everything up and put belt back on. I guess it makes sense that there should be some difference between the time that the pump goes and the cylinder is a TDC right?

Sorry, forgot to mention that yes i did check spark and there was none.

I don't know. most people just make a mark on the engine and put the new HES in the same spot as the old HES. Sounds like you followed the manual though, so I'm sure it's OK.

Two more questions. Do you have a rider information display (RID). It shows fuel, oil temp, and gear. If so, does it turn on and off when you raise and lower the sidestand with the key on? If not, do you hear the fuel pump cycle when you raise and lower the sidestand with the key on?

Two failed coils seems unlikely. I believe 7.5 K ohms is the usual reading.

The HES position is irrelevant to whether it sparks or not. The adjustment range is only about +/- 3 degrees.

Since you don't have an RID it is hard to tell if your Motronic is powered up. Did you measure +12V at the Motronic relay Pin 3? And then try a jumper in place of the Motronic relay?

No my RID does not have all those features. I have gas level, neutral light, turn signals, high beam, ABS, oil level and battery. The pump does cycle when I raise and lower the kickstand.

I did measure motronic relay pins and I am getting 12v between pin 3 and 5. I did try a jumper and switching the pump relay and motronic relays. No luck. I tried out a brand new ignition coil and you are correct that the old ignition coils are good.

I received my new ignition coil today and unfortunately it did not resolve the issue. I guess I have 3 working ignition coils now. So i am back to it being the motronic control unit. I don't think I have a way to get my hands on one just to test if mine is bad. Does anyone know of a way to bypass the motronic control unit to test the spark? Should I open the unit up to see if there is any visible damage?

My other question is that I know that the clutch sensor unit is bad since the bike won't start when clutch is pressed and bike is in gear. I did test the bike at one point by jumping the two wires in the plug, but it did not make a difference. Since then I just re-plugged the wire to the sensor. I figured since the bike is in neutral there shouldn't be a difference anyway. Should I keep the wire jumped while testing?