[keitih89]

I'm planning to replace the crank position sensor on my 2008 1098 with original CPS. I'm having an issue with the rear cylinder not firing. I have spark, fuel, & compression. I am now thinking CPS is firing the coil at the wrong time.

I was wondering if the 848/1198 CPS is compatible with the 1098. There are two different part numbers and as far as I can tell, the only difference is the wire exits the side of the 848/1198 sensor instead of the top like the 1098 sensor.

848/1098R/1198: 55241321A
1098: 55240201A

 

[EL Twin]

I would expect if the front cylinder is firing OK the problem won't be the crank sensor. There is only one trigger point for the sensor and the ECU works everything else out from that one single signal.

 

[keitih89]

I would expect if the front cylinder is firing OK the problem won't be the crank sensor. There is only one trigger point for the sensor and the ECU works everything else out from that one single signal.

I didn't know there was only one trigger point. how does it know to fire each cylinder with one trigger point?
I've seen reports of bad cPS's fixing this problem. Another symptom is when I hit the starter, it will keep cranking until I key off. Usually it stops after a certain number of tries. That has me thinking CPS because it's not correctly counting the number of cranks.

Here's my thread in the 1x98 section for everything i've tried to diagnose: http://www.ducati.org/forums/1098-1198/63859-p0351-code-vertical-cylinder-not-firing.html

I was hoping you'd see the thread and chime in with your expertise.

 

[keitih89]

I just checked the CPS function in the manual and it says: This sensor (1) is of the inductive type: it faces the timing gear and is capable of reading the 46 teeth and the 2-tooth gap.

I'm thinking its either just out of spec or on its way out and not reading all the teeth properly. Especially since it's not counting revolutions to stop cranking.

 

[orionengnr]

I'm not sure about your first issue--when I had a bad CPS, I had no spark, period.

I was also experiencing the "cranking after button release" issue, and was informed that this is a "feature". You only need to touch the button, and don't need to hold it down. The engine will start and the starter will dis-engage.

 

[keitih89]

I'm not sure about your first issue--when I had a bad CPS, I had no spark, period.

I was also experiencing the "cranking after button release" issue, and was informed that this is a "feature". You only need to touch the button, and don't need to hold it down. The engine will start and the starter will dis-engage.

I'm hoping the CPS is just getting weak or out of adjustment causing it not to read all the teeth. I'm thinking the horizontal cylinder fires off the 2 tooth gap in the timing gear so the CPS can read that but not all the other teeth, so the vertical cylinder is firing at the wrong time.

Yes, I hit the button once and it just keeps cranking. And its not the battery because it's fully charged and it cranks quickly.

 

[ApexmotoInc]

I can confirm that the CPS can cause an 1198 to run on only the horizontal cylinder. What will happen is the bike may start correctly, running on both, then it drops the vertical cylinder.
The vertical cylinder may fire from time to time or not at all, depending on the CPS signal.

JPDiag shows Crank position sensor A error.

Replacing the crank sensor fixed the problem.

I can be difficult to diagnose, as when the CPS is failing and not 100% failed, it can cause the ECU to do all sorts of strange things.