Had two leaky injectors, smelled gas before I could see the problem.
Removed the injectors and went to a shop. They made new o'rings in the back, should withstand CO 110 gas (europe). The old o'rings were not damaged, but as long as I've removed them.. why not change them. My engine has about 60K miles on it (100K km). Also cleaned the gunk that was there (not much, but why leave it there).

Back home, used some left over 5w30 oil from my previous car o the o'rings, slit the injectors in the fuel rail carefully, and place the o'rings on the engine. Then, guided the fuel rail on all 4 injectors.

I would say a 1 and a half hour job, if you are not very experienced. Just take it slow and you will be fine. Oh and also tighten the Fuel Pulsation Damper because I forgot that and as soon as I put the ignition on, gas started spraying. Fixed.


edit: not FPR, but FPD

 

I've just experienced the exact same leak from cylinder 3 of my injectors as in the picture. From the hole in the plastic connector.

Mine is a F20C2 2004 model with 85k miles.

We first replaced all the seals with genuine Honda seals. All 3 seals on all 4 injectors.

Initially we thought this had fixed it. But no, started leaking again from no.3 cylinder injector.

So the garage moved the 3rd injector to the 1st front injector with more new seals. Still leaking from the hole in the side of the injector.

So I have now been looking for a replacement injector, and have just ordered a full set of OEM Honda injectors from BalladeSports.

I'll hopefully sell on my good used ones for spares and recover some money.

I would like to know why this hole is leaking...as it has clearly happened to the OP.

I have never had any problems with injectors before on any Honda I've owned over 15-20 yrs
?

 

Just wanted to thank @BalladeSports for helping me out with their excellent service.

I ordered a full set of replacement OEM injectors (which includes the seals for each) for not much more than 1 OEM injector would have cost me in the UK.
They shipped the order the same day, and I received them in about 7-10 days here in the UK. Customs delayed the final delivery as I had to pay about $20 duty/tax
(Thanks for all your help BalladeSports)

Highly recommended!!

I'm getting them fitted in the next few days. Hopefully it will be all resolved then.

 

Now all fixed. New injectors did the job.