89 corolla sr5 making terrible noises!!

[SHarks909]

After my car warms up between 2,000 and 3,000ish rpms Only under load I get a terrible knocking rattling kind of noise it has been going on for a while but lately it has been much louder and much worse I have also seen a hit to my mpg my last average being 17 mpg mostly highway >.< I'm thinking it could be the front main bearing or the crankshaft itself or the aux. belt tensioner or the connecting rods (but I think this is unlikley due to the fact that it has been ongoing and the inside of my engine is still inside) I've heard that alternators can even make noises like that if they are unhappy any thoughts? Is my car going to die soon? Help would be appreciated.... It's being going on for a few months but has recently become much louder and much worse It turns heads and I can feel vibrations through the gas pedal

[REN69]

Your best bet, take it to a mechanic and quick. We can't tell you what's wrong without actually hearing it or driving it.

[SCT]

Yea, best bets are to take it to a reputable shop. Knocks can be from very simple to solve to no hope to solve, depending on severity. Earlier you can take it, the better especially when the noise and knock progressively gets worse.

[1991corolla4afe]

My sedan does the same thing but only when it's cold out (less than 60 degrees) and has been doing so for over 11000 miles.