Have you experiences this issue?

[Phil Gti 11]

I had my injectors proffesionally  reconditioned/ultra sonic clean and tested with a good spray pattern. I replaced all the O-rings. Before I assembled it I cleaned all the inlet ports with emery paper. After refitting the injectors and making sure they were fully home I bolted down the fuel rail and started the engine and let it run for a few minutes. The fuel injector closest to the cam belt started leaking a little fuel from the nozzle end at the inlet port of the manifold. It was pooling in the base of the port and running down the side of the inlet manifold.

So I removed it, made sure the inlet port was smooth and clean. The O-ring wasn't damaged. I sprayed a little WD40 on the O-ring and re seated it. Started the engine again and sure enough a small leak of fuel again. The other 3 are fine. Any suggestions or recommendations?

[petert 585]

Wrong size o-ring? Did you damage it initially by incorrect fitting or inserting without lube?

[Phil Gti 11]

O-rings were ordered against injector serial number. Brand new pack of 10 Bosch ones. I used silicone spray before fitting 1st and second time. Definately right size, hence only 1 of 9 possible  O-rings leaking. 

[welshpug 1,655]

Are the injector clips present?

[Phil Gti 11]

Yes. nothing is missing. All injectors are pressed home equally into the fuel rail and inlet manifold. Fuel rail bolts to the inlet manifold in the correct positon easily.

[Zetec7 4]

Was you a bit heavy with the emery paper on that one?

[Phil Gti 11]

I don't think so. Just enough to remove dirt build up in all the inlet manifold ports and so that they were smooth. I have a vernier gauge and will see if there is larger measurement. If so, I will try painting the port with same paint used for the manifold to see if a thin build up of paint will give a tighter fit.