Kitchen outlets raise to 130 vac when coffee pot or toaster is on. At the same time bathroom lighting dims and voltage drops by same amount. About -112/113 vac I’m a little confused after checking neutral to ground ok - reading taken from neutral to hot. Have not isolated circuit breaker as of yet. No voltage at neutral to ground. Are there two circuits or more being fed power?
You May Have a Lost Neutral
If voltage only goes down, that is an indication of overload. But when voltage goes up in one place and down in another, that is an indication that your neutral is not working properly. Since you show 0V neutral to ground, the problem is very likely outside your home. In other words, a utility company problem.
Since you have a multimeter, one more thing to check:
If you have any 240V plug-in appliances (e.g., electric dryer), check the voltage at the receptacle. You should have a consistent value (~240V) between the hots and a nearly identical value (~120V) between each hot & neutral. Then see how that changes when you turn on any relatively large loads (like coffee pot or toaster). If you see a similar change - i.e., one side up, one side down - then that confirms a likely neutral problem.
CALL YOUR ELECTRIC UTILITY
Tell them you think you have a neutral out. They should treat this as a serious problem because of the problems it can cause. They should send someone out fairly quickly to check things and, assuming the problem is on their side (pole or meter) they will generally be able to fix it pretty quickly. If they determine it is not their problem then you need a licensed electrician to check from your meter to your breaker panel and figure out what is going on.
Meanwhile, I highly recommend you unplug any sensitive electronics (computer, TV, etc.). While many devices are able to handle a wide range (e.g., 90V to 240V), many can't and even those that can may not like the ups & downs.
Call the power company RIGHT NOW and report an outage
This is the classic symptom of a lost neutral. Each leg of your power is NOT 120V, yet the two poles add up to 240V, and voltage varies as load varies.
90% of the time, the lost neutral is out at the electric pole or service drop, because that is up in the weather, moving with the wind, etc.
The power company will fix this quickly and for free, unless there's been a recent calamity such as an ice storm that has them all working double shifts, and even then, it will be given the same priority as weather damage (since it may be exactly that).
It's also possible it could be in the meter or service panel wiring (if it affects the whole house), or along the shared neutral of a multi-wire branch circuit (if only one MWBC is affected). But my money is on the pole.
Do not hesitate or second-guess on this. I have seen a whole complex affected for a whole week because nobody got how serious it was.