rewiring to fix open ground?

well i thought it was fixed but after spending more time with it i realize its not. i hooked the ground up right in the outlet so im guessing the problem is somwhere between the back of the outlet box and panel box.

What did your little three prong tester say?

i didnt use it when i first added the ground just turned the amp on and listened. later after trying to play though the amp and getting the noise i used the tester and it still said open ground

Who ever ran the ground may have just gone to plumbing, cast irom stack or copper pipe, if the plumbing has been upgraded to plastic since, then the ground may haver been lost.

In a lot of old houses I have seen where someone added an outlet or did some wiring and used a two conductor cable and a ground for the new work. They go as far as they can figuring someday I will be upgrading and at least I will have a little bit of it done. They also go around and replace the old two prong outlets with 3’s for looks and convenience without adding the safety ground back to the panel.

The only way I know to correct your problem is you have to figure out how your wires are run and what is feeding what and start at one end and work your way back to the point they tied into old and omitted a safety ground, and then fix it from there back to the panel. That could be easy or it could be hard. Lots of time the knob n tube is left to overhead lighting from the switch to the light on the first floor as people don’t want to ruin fancy plaster ceilings and have no access from above or below. In rewiring an old place the first floor mostly can be got from the basement and the second floor from the attic. They find a good place to run a chase up to the attic in a closet or something to get between floors. One of the biggest problems I have found with real old houses is the outside walls often sit on a big beam. To get a wire up into those walls from below you have to drill an angled hole sometimes. Old houses also have fire breaks in the walls that make it hard dropping wires down between the studs.

The reason I mention all this is even if you hire a pro to do the whole house these are the problems they will face also. As you are doing stuff on your house be thinking about the best ways to run wires and how you may want that done.

At this point I recommend taking a day and doing the tests in #18 to get an overall idea of the problems you're having.
This info may influence the timing and extent of your repair/replace decision.

Just mapping the outlets may take you a day.
In each room you can say, e.g., upper NE room, 1st. outlet on NW wall, 2nd, etc., 1st on SW wall, ceiling light, and then map each to the load center.

Frinstance, index to circuit breakers for a split bus panel

a/c, 27 & 29
basement lighting, 25
basement west wall outlet, 20
bathroom GFCIs, 22
bathrooms, upstairs, 24
breakfast area outlet, 18
cooktop, 12 & 14
cooktop light, 17
room, 24
dining room outlet, 18
dishwasher, 19
disposal, 19
Dryer, 4 & 6
family room, 25
fan, kitchen, exhaust, 17
foyer, 21
fridge, kitchen, 17
front porch, 21
furnace, 23
guest room, 22
kitchen, 25
kitchen ceiling light, 20
kitchen overhead fan, 20
living room west wall outlets, 20
master bedroom, 24
mudroom outlet, 18
outside outlet, 18
oven, 8 & 10
pond pump, 26?
porch, screened, 25?
room, 22
sump pump, 21
washing machine, 18
whole house, 3 & 5

Breaker number/amps

15A: 20 to 25
20A: 17 to 19, 26
30A: 4, 6,8,10, 29
40A: 7, 9, 11 to 14
50A : 3, 5
* * * * * * * * * * * * * *
Circuit Breakers

3,5 whole house except dryer,
oven, stove, air conditioner
4,6 dryer
8,10 oven
12,14 cooktop
17 kitchen outlets, fridge
18 washing machine,
dining room outlet, mudroom outlet,
outside outlet, breakfast area
19 dishwasher,disposal
20 living room west wall,
kitchen ceiling light, kitchen fan,
basement west wall
21 sump pump, front porch, family room,
foyer
22 upstairs room, guest room,
bathroom GFCIs
23 furnace
24 master bedroom,
both upstairs bathrooms
25 family room, back screened porch,
kitchen, basement lighting
26 screened porch, pond pump, kitchen
27, 29 air conditioner

There's also a way to find the order of outlets on a branch circuit by using a 1 kw load (hair dryer, room heater, worklight) and a multimeter on the 200 mVac scale.
It's tedious but it works.