1996 California 1100i running problems

Hoping someone can help me resolve a few issues i have with the California, I recently acquired the California and it ran ok for the first 100 miles or so then it started to cut out on the left cylinder then refusing to start or idle, plug on the r/h cylinder a good colour but the left soots up and appears to inhibit a good spark, as the control unit is on the r/h side there appears to be very little adjustment on the left cylinder unit, I’m wondering if this is an injector failure or something more serious in the injection system?!.. I must point out that the bike looks as though a few previous owners have been fiddling with all sorts of things on the bike, even drilling extra holes in the top of the air box at sometime this was taped over to re seal it and is still taped up. When running the bike pulls strongly and doesn’t miss any beats. Can’t seem to find a workshop manual for this model anywhere as it’s a bit unusual (it has air in this front forks for example), so if anybody has a photo copy I be greatful of a loan or I can pay for a copy.
My other Guzzi (750 Nevada)thankfully is running so rides out are still going ahead as I live on the NC500 route.
Thanks in anticipation of any help you can give me, cheers

Most manuals, parts books, wiring diagrams can usually be found here
https://www.guzzitek.org/gb/accueil_gb.htm

Sorry for the late response - only just came across your post.

You have quite a few things to check out.

  • Correct plug grade?


  • First check that you have a decent spark. The plug leads can come loose in the coils.


  • Are the plugs sooty/oily on one side only, or just the left plug generally sooty? This will give you a clue about injectors.


  • Check the injector connections.


  • If the plug colours look OK, then check the valve clearances. My 1100i had been on a sidecar outfit and PO had never checked the inside head! (The one nearest the chair)


  • Try tuning the and balancing the throttles - always pays dividends in smooth running and trouble free starting.

If all else fails you can service the injectors or get them serviced for a modest fee.

I am having a recent similar episode on my 1100i, although it has done many thousands of miles superbly. I suspected a fuel contamination problem, but have failed to fix it so far. Now doing a complete fuel pipe change. Could be E10 or diesel affecting old fuel pipes. Your problem sounds to be one cylinder only, but could be a similar to my bike’s behaviour.