2003 cbr954 not starting
 

so ive had the bike for about 4 months and when i got it the previous owner had made custom ignition and kill switches and a couple other things so i tore the bike down and the harness out and fixed all the bad wiring i could see and put the stock ignition controls on and wired in a new ignition (from a cbr600) and with a zener diode (with no resistor) to turn the system on. The thing is that is ran very smooth before i did all this and i changed the spark plugs too but now my problem is that it will only start after a week of sitting and it will only run with the help of the throttle and if it dies it wont start again. Its also fouling the new plugs i just put in and i have codes 8, 9, and 12 is this common or what should i do i am very limited on tools now too

Might be worth you downloading a copy of the workshop manual. It has the codes in there, Section 5-10 & 5-11. No matter what bike I have, if I can get a Haynes & an official workshop manual, I do so. Both are always useful to have to hand.


https://www.manualslib.com/manual/81...02.html#manual


So Code 8 is:




Loose or poor contact on TP sensor


connector


Open or short circuit in TP sensor wire


Faulty TP sensor


Code 9 is:




Loose or poor contact on IAT sensor




Open or short circuit in IAT sensor wire






Faulty IAT sensor


And Code 12 is:
Loose or poor contact on No.1 injector




- connector Open or short circuit in No.1 injector wire


Faulty No.1 injector


Sounds Like there's a load of things that aren't connected properly, or haven't been reconnected. Probably means you having to dive back into the wiring loom to check all those connections.

Yeah, I would bet the connectors aren't seated properly. Most things like this are a really simple fix when it didn't do it before