So...its a simple question with my different answers... One person told me to use gas, another said oil, vasoline, and grease, spit, WD40....

So what the hell do I use? Haha, the people were arguing petroleum based products will cause the O-Ring seals to swell.

 

I've used this stuff on fuel injectors many times in the past. Works very well!

 

my factory manual says use engine oil