I've been using vaseline on injector O-rings and also the ones that goes into the fuel rail.
Do not use silicone grease of any sort. If it gets into the fuel rail (which it will, trust me on that), will subsequently gets into the emissions control components (upstream O2 sensor, CAT, etc.) and will ruin them over time.
Also: these o-rings (seals) are made of viton, and 100% resistant to mineral oil products.
Do not use silicone grease of any sort. If it gets into the fuel rail (which it will, trust me on that)
Yes and no.
I am fully aware of silicones nasty habit of poisoning Oxygen sensors, but you're not globbing it on, your putting a extremely thin film on, not enough to see, or wipe off. I've done it on some part into plenum o-rings that refused to go in, and injector o-rings, to no ill effect of oxygen sensors.
Super Lube grease is what Trav suggested I use when I installed my injectors. It worked fine.
Thats what i include with injectors, its a non silicone PTFE semi clear grease. Vaseline, oil and even WD40 work fine also but i notice after a few years in service the injectors come out easier with the PTFE grease, the PTFE stays on the o rings.