Im looking at buying a cheap beater car and found this 1999 neon. Went out to look at it and when i turned the key to power everything before starting, a loud noise/rattle sounded.. but if you go through all the key "clicks" slowly, it starts up just fine and has no issues. It sounds like its coming from the trunk.


Also, It is unusual for the ac and heater to go out on these cars?

 

Fuel pump? it comes on when the key is turned on

 

Muffly rattle maybe. One of my mounts rusted off and the muffler was sitting on the rear control arms. When I'd start the car it would rattle a little... more of a dull muffled mattalic thump. As you drove and it pumps you could also hear it.

Front engine mount and engine dampener where shot so engine would tourqeu more than it should during ignition and that moved the muffler.
My car only had two muffler hangers installed. One by the rear drivers side wheel and another near the bumper.

Put your ear to the muffler and make sure it's not touching anything... then have them have someone start it. You'll hear, smell the engine.
You wanna do key dance and see if there any pending codes.

Find out when/if water pump, timing belt, pully/tensioner have been changed. Check collant for oil and vice versa. If they'll let you check the plugs and do compression test. Your gunna have allot of fun with that car