No, there most likely is not. The majority of 318i/is/ti came without an amp and have a basic 6 speaker setup, whereas the others have 8 or more. If you have 3 speakers up front (two in the door, one in kickpanel) then you should have an amp. Only speaker in the door indicates no amp. The amps location is in the trunk is behind the bulge in the carpet by the taillight on driver's side.
<span style='color:gray'><span style='font-family:Courier'>1995 e36 3 Series RIP
1999 e46 3 Series BURN IN HELL
2000 MR-S Roadster= Current</span></span>