1996 Cali 1100i ECU lamp

Recently my 1996 California 1100i developed a rather weird fault in that it started back firing, running off a plug and then coming back on again, and sometimes when you turned the ignition on, there was a “puff” from one one of the cylinders even before you hit the starter button. I noticed that the lamp beside the rev counter would also give an occassional blink.
I traced the fault eventually to the rev sensor on the engine casing at the fly wheel. When I removed it, it was covered in crud and fragments of metal. Once cleaned off and put back in place the bike was running as it should again.
However, I now notice that the ECU lamp is constantly flickering very quickly, albeit very dimly almost in time with the ignition.
My question is, has it always done this and I never noticed it before, or is this something else I need to look in to?
I look forward to hearing from you.
Guzzi LED.jpg

So that’s what it is for :wink:

I haven’t checked the LED, but have a similar problem.

The crud is supposed to be collected by a magnet; cunningly placed so that it is either an engine out job or remove the starter (according to Guzziology). Not a frequent task.

However, the misfire is baffling. I have retuned and checked the TPS; which is at the bottom limit. I will adjust today to mid-range. Plugs are good and the misfire is intermittent.

In your case you can check for air leaks and do a retune. Alternatives are failing crank position sensor or poor connection somewhere. Unlikely to be the CPS unless you have disturbed it. (Might have some crud on it).

I can trace the start of my problem back to a refuel from a local garage and suspect fuel contamination - they have been lax before, deal in mostly diesel and have a water problem with their tanks. Coincidence maybe, but I am emptying the tank and refilling with good unleaded to check. Work in progress …

Simple adjustment of TPS I don’t think. How do you loosen the rear 7mm screw as it is so close to the clutch housing?

Ordering a small socket. (Flex sockets are impossible to fit).

OK. Too confident by a mile! Crank Position sensor was heavily “whiskered”.
CPS_Whiskers_20210601.jpg

Look at the spark plugs - inlet valve side is black and glazed.
Plugs_In_side.jpg
Exhaust side is fine.
Plugs_Ex_side.jpg
Will do a fuel drain & refill and plug change and will report back.

Does contaminated fuel need a new thread?