[Chevelle722]

I have a 1972 chevelle. The rear side marker lights work and the front head lights work, but when i turn the running lights on, the back brake lights do not go on, the reverse lights don't go on, and the brake lights as i press on the brakes, the lights are lit dimly. also the hazards work. today i replaced all of the fuses in my fuse box that were 20A but im curious, am i missing a fuse? do one of the other fuse's power the brake lights? i replaced the fuse that says "stop" so i was assuming that the stop light fuse also powers the running brake lights but i could be wrong. also the dome light stopped working, i also thought about the brake lights just needing to be replaced, but if so why would the hazards work and why would the brake lights work but be very dim? i had the car taken to the mechanic shop and before i gave it to him, all of this worked, he says im missing a fuse or something, anyway sorry for the long posts, i am just trying to give as much detail as possible. thank you. also another question the car mis fires badly and i tested all of the spark plug wires while the car was running and the wires had electricity flowing threw them could they still cause the car to misfire? when i rev it really high the mis firing fixes itself randomly it just mis fires randomly and when i rev it, it goes away for a while then comes back again randomly. could it be the fuel filter maybe? anyway that's all i got for now, thank you again guys.

 

[NickeyChevelle]

Start checking grounds -- first check the ground wire that attaches to the trunk "tail lamp panel brace" that the trunk latch fits in.

 

[novaderrik]

pull apart every ground wire you find on the back half of the car, clean them, and screw them back down.
doe the tail light bulbs ground thru the socket to the tail light, or do they have a separate ground wire? when i first got my 71 Nova, the plugs fit in the tail light housings kind of loose and the lights would decide to not work at random times, so i cleaned them up and bent the locking tabs out for a tighter fit and never had another problem for the rest of the 5 years i had that car.

 

[Chevelle722]

My mechanic cut my carpet out to patch holes in my floor pan and im thinking he did something to the wires. I work a lot but i will look into the wires and bulb housing. Thanks a lot. Any idea on the misfiring question?

 

[Chevelle722]

Also i do not have a clue about the grounding wire question i can take a pic of the trunk inside,to help u get an idea if you'd like.