Hello, I've just signed up from Italy. I own a 2004 Honda Jazz LS, 1.2 litres engine. It was last overhauled by Honda in 2012 at 80.000 KMs with all the scheduled maintenance for that threshold, now it's approaching 100.000 KMs.
Never had any problem at all until a couple of weeks ago. The engine failure light blinked for about 30 seconds while I was doing about 70 Km/h, then switched off again before I had the chance of pulling over and stopping the engine. I immediately took the car to a workshop, they plugged in the diagnostic tool and found it had logged what (after a bit of research) I think would translate as "random misfire" ("misfire on an unidentified cylinder" was what they told me; sorry I don't have the exact code). They guessed it could be the spark plugs or the coils. So we decided to check and replace the plugs for starters (meanwhile the failure light had blinked a second time, again for about 30 seconds and again switching itself off afterwards).
The workshop swapped all 8 spark plugs which, they told me, were pretty worn out anyway (which is surprising since they supposedly had been replaced at 80.000 KMs so they were middle age in terms of mileage).
Since then the incident has happened twice more, in the same way (engine failure light blinking for a few seconds, when cruising at about 70 Km/h, then switching off by itself).
The light never lit solidly, it always blinked, and it never stayed lit or continued blinking after those few seconds.
Now, I am concerned it might be something serious (serious enough to risk damaging the engine or the catalytic converter, or to require costly repairs, or cause the car to stop on the road).
I have done a bit of Googling and the more recurring causes for this inconvenience seem to range from a simple valve registration to an injection problem to a fuel system problem to even worse scenarios. What concerns me the most is the blinking. Most people who had this problem reported a solid light. And I've read that blinking generally means a serious problem with immediate risk of damage. It's the only car in the whole family and I have to attend a distressed relative so I can't afford to stop the car for precaution, but I cannot for the same reason risk damaging it.
Can you help? What would your guesses be?
Thanks and sorry for the lousy English.

EDIT: after further research, I believe my problem could fall into this scenario: http://www.straighttalkautomotive.com/OBD2/P0300.html
Multiple random misfire... can be anything... so far I've just ruled out the spark plugs... from what I can tell the engine is running fine, albeit I've noticed it has become more noisy over the years, for example when cruising at certain speeds in 5th gear there is some kind of ryhtmic "humming"... but that's about it, it never seemed to run on 3 cylinders or stutter.

 

Hi,
My first Jazz post from the UK
My 1.4 EFI Jazz started cutting out while driving with the orange engine system light blinking erratically, the engine would splutter and then continue for a bit eventually and stopped .
It would restart after 15 mins of switching off. After pushing my luck for a week it now wont start at all and the green immobilser light is constanly blinking.
Has anybody else had this experience ?

 

As this does not look like the same problem as mine, despite the blinking MIL, I suggest you start a separate thread. Anyway, given I've gotten no responses so far, I don't know if it would do anything.
By the way, I purchased a cheap OBDII scanner and was able to identify a specific problem code, P0302, misfire in cylinder 2, it's probably one or both the coils in that cylinder.
Since you're in UK I suggest you join the UK based clubjazz.org forum, they were instantly able to help me.