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New Hall sensor only firing one sensor

mark from maine

New member
New Hall sensor only firing one cylinder

Bike is 98 R1100RT. 33K miles. I replaced a good original hall sensor with a new hall sensor. Bike was running fine with the old one. Started bike after installing new one and bike is only running on left cylinder. Removed pulley and rechecked timing by setting engine at top dead center and listening for fuel pump to switch on, it does. Checked to make sure of proper placement of pulley tab, it is correct.

Put everything back together and still only running on one cylinder. Changed sparkplug, made no difference.

Guess I fixed it till I broke it.:)

What could it be?

Thanks,
Mark
 
Last edited:
Bike is 98 R1100RT. 33K miles. I replaced a good original hall sensor with a new hall sensor. Bike was running fine with the old one. Started bike after installing new one and bike is only running on left cylinder. Removed pulley and rechecked timing by setting engine at top dead center and listening for fuel pump to switch on, it does. Checked to make sure of proper placement of pulley tab, it is correct.

Put everything back together and still only running on one cylinder. Changed sparkplug, made no difference.

Guess I fixed it till I broke it.:)

What could it be?

Thanks,
Mark

I'd like to think this is not possible, I'd like to think that the HES will fire both sides or neither.

Any chance you didn't reconnect a fuel injector on one side, or something else obvious?

According to my reading of wiring diagrams, both plugs and both injectors are fired simultaneously. I suppose it's possible that the MCU could suppress both of these when cyl #2 is in firing position, if it is missing 1 of the 2 signals from the HES, that would be very useful info.

Any chance you could do an oscilloscope check on the 2 signal wires from the HES? The orange wire is TDC, the black wire is BDC, and both should show a pulse train, dipping from 12V to 0 once per rev. This is not so easy to do, but I'd be grateful for the data.

If this is too complicated, and if you then feel forced to into the obvious solution of going back to the original HES, could you do a bench test of the new one, or have the dealer do it? It would be nice to know if it really has one bad sensor. The bench test is fairly easy, if you're interested.

Good luck
 
After further searching on the forum I saw where someone had a similar experience and the cause was the throttle cable was pulled out of its ferrule. Out to the shop, took a look and sure enough the right throttle cable was out of it ferrule. Dropped it back in and she purrs like a kitten.

Someone please give me a dopeslap and straighten me out will ya?

Thanks,
Mark
 
I wanted to say in the title that with the New Hall sensor the bike is only firing on one cylinder. Sorry to mislead.

Mark

Your original was clear, no misleading, I think. I assume that you assume one sensor in the new HES is bad, which could be true, and could be the cause of one cylinder not firing (though I hope some other cause will be found). It would be useful to me to know.

If you are willing to do some diagnosis:
-which cylinder isn't firing?
-does it have spark?
-if you are comfortable checking fuel injector spritz, is it there?
-have you checked for any obvious problem with this cylinder? Spark plug wire firmly connected each end, electrical connector to injector good, etc?
 
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