Can a 1995 Honda Civic engine fit in a 1999 Honda Civic?
Yes, but it is a federal offense to put an older engine into a car that is newer.
I assume you are talking about a 1996-2000 Civic EX and a 1999-2000 Civic Si. If so then yes, people do it all the time and practically every part will fit and work on your EX model, especially if you have a 1999-2000 Civic EX. Interior/exterior pieces, suspension, engine parts, etc. That's the great thing about hondas.
The engine oil capacity for a 1999 Honda Civic is 3.5 quarts. (Just in case you meant transmission fluid - since you mentioned it's an automatic - the A/T fluid capacity is 3.0 quarts. Note, if you have a GX or HX model with a Continuously Variable Transmission, it will take 4.0 quarts of Honda CVT fluid).
the 1999 civic was released a year after the 1998 civic and has an "e" in the suffix whereas the 1998 civic has a "d" in the suffix. Also, the 1998 Honda Civic dX shoots flames from it's exhaust pipe. This was deemed "so nineties" by 1999 by the National What is Cool and What is Not (NWCWN) Board of Directors it's in 1999 national caucus. Sources: Common Sense Former NWCWN Chairman I'm 90 years…