I've replaced fuel filters before on Civics as well as my gen1 integra (mine is a '93 Civic DX sedan). Never have I experienced something like this. Of course, it could be due to something entirely unrelated, that I could have accidentally knock loose while working on the fuel filter too.

I opened the hood and I can't make anything out but the usual engine noise (mine has a harsh whispery tone It seems to be noticeable from inside the car and during idle or lower rpms. Perhaps the engine noise at higher rpms drowns it out or maybe the noise does truly go away. The car runs fine and there is absolutely nothing different in the way it drives from what I can tell.

I'm attaching a sound byte of the noise. It's not quite the same as what I hear in person but pretty close.
I would describe it as a mini, muffled diesel engine.

Can someone please help me out? (noise.zip contains an mp3 of the noise)

Btw, the car has been running great with no abnormal noises even after replacing the air filter and spark plugs in the last few months. I "just" replaced it today. Here is a picture of the installed filter:

 

Looked under the hood again to see where the noise was coming from. Again, with the engine running it's not really audible under the hood. I felt around to determine if I could detect if there was any vibration.

I did feel a pulsation in the hose (with the red letters above) going from the filter to the fuel rail. The repeating pulsation seems to match that of the frequency of the noise I hear from within the cabin.

Can anyone tell me if that's a bad thing? could something be clogged?

 

I'm out of ideas. More and more, I think it's something to do with the engine noise... like the vibration of the crank that I didn't notice before or got louder since before the fuel filter change.

I can't see how a fuel filter replacement would cause any of this.

 

weird.. have you try reinstall your old filter and see if noise goes away??

 

Update: I replaced the noise.zip (containing the *.amr file) with one that has an mp3 of the noise.

One question for everyone. When you shake a new fuel filter, is there supposed to be something slightly loose inside? I believe mine did and I didn't think anything of it. I'm wondering if this could be causing the slight knocking noise I'm hearing.

I recycled my old fuel filter away so I can't test it anymore, unfortunately.

 

Loose valves, or exhaust leak maybe? The file is not clear. It's not going to have anything to do with the fuel filter.