My oven has recently started throughing sparks from the inside .theres what looks like a metalic covered cardboard cover on the right side that has been burned. Iturned on the oven once without the turn table and the problem started then .can it be fixed?

see this steps and fix it. God bless you
If you see arcing or sparking inside a microwave, turn unit off immediately. Arcing can be caused by having something metal in the oven cavity touching a side, an oven shelf is touching the side of the cavity, an oven shelf support has broken, microwave waveguide, or bad magnetron.
If your microwave has a shelf in it, and you do not use it, keep it out. If one of the shelf supports breaks or comes out, the microwave will arc where the support was. You will have to sand the spot down, paint with appliance paint and re-install support. If the shelf shifts on the support and touches the side it will arc.
Your magnetron waveguide will either come out of the top, or side of the oven cavity. Some will have a stirrer in it(mostly top waveguides) with a panel over, or just a cardboard type cover over it. Over time, the stirrer cover can become warped from the heat which will expose the stirrer's metal shaft which will then cause sparking. These covers and stirrers come in a kit and can be replaced from inside the oven cavity.
Your cover over a side waveguide is coated with a substance on it, and overtime this coating can come off from the heat and moisture in the microwave. These waveguide covers are very easy to replace from inside the oven cavity. Touch up any paint that may have chipped or come off because of the arcing.
If your waveguide cover and/or stirrer are all OK, then the spark is coming from your magnetron. The antenna on your magnetrom has overheated and burned, sending the microwaves out at the wrong angle. If you catch this microwave oven repair early enough, you can usually get by with just replacing the magnetron. If the arcing has caused servere damage inside the waveguide, you will need a new microwave. Waveguides are not replaceable and most you can barely see into them, let alone sand and re-paint. In this case of microwave oven repair, when you remove the magnetron, you will see the burned antenna, or your magnetron will fail the test below.

see the guide for test the magenetron and another component.

see this next steps. God bless you
If you see arcing or sparking inside a microwave, turn unit off immediately. Arcing can be caused by having something metal in the oven cavity touching a side, an oven shelf is touching the side of the cavity, an oven shelf support has broken, microwave waveguide, or bad magnetron.
If your microwave has a shelf in it, and you do not use it, keep it out. If one of the shelf supports breaks or comes out, the microwave will arc where the support was. You will have to sand the spot down, paint with appliance paint and re-install support. If the shelf shifts on the support and touches the side it will arc.
Your magnetron waveguide will either come out of the top, or side of the oven cavity. Some will have a stirrer in it(mostly top waveguides) with a panel over, or just a cardboard type cover over it. Over time, the stirrer cover can become warped from the heat which will expose the stirrer's metal shaft which will then cause sparking. These covers and stirrers come in a kit and can be replaced from inside the oven cavity.
Your cover over a side waveguide is coated with a substance on it, and overtime this coating can come off from the heat and moisture in the microwave. These waveguide covers are very easy to replace from inside the oven cavity. Touch up any paint that may have chipped or come off because of the arcing.
If your waveguide cover and/or stirrer are all OK, then the spark is coming from your magnetron. The antenna on your magnetrom has overheated and burned, sending the microwaves out at the wrong angle. If you catch this microwave oven repair early enough, you can usually get by with just replacing the magnetron. If the arcing has caused servere damage inside the waveguide, you will need a new microwave. Waveguides are not replaceable and most you can barely see into them, let alone sand and re-paint. In this case of microwave oven repair, when you remove the magnetron, you will see the burned antenna, or your magnetron will fail the test below.

see the next steps and follow with common sense: God bless you
Microwave is arcing If you see arcing or sparking inside a microwave, turn unit off immediately. Arcing can be caused by having something metal in the oven cavity touching a side, an oven shelf is touching the side of the cavity, an oven shelf support has broken, microwave waveguide, or bad magnetron.
If your microwave has a shelf in it, and you do not use it, keep it out. If one of the shelf supports breaks or comes out, the microwave will arc where the support was. You will have to sand the spot down, paint with appliance paint and re-install support. If the shelf shifts on the support and touches the side it will arc.
Your magnetron waveguide will either come out of the top, or side of the oven cavity. Some will have a stirrer in it(mostly top waveguides) with a panel over, or just a cardboard type cover over it. Over time, the stirrer cover can become warped from the heat which will expose the stirrer's metal shaft which will then cause sparking. These covers and stirrers come in a kit and can be replaced from inside the oven cavity.
Your cover over a side waveguide is coated with a substance on it, and overtime this coating can come off from the heat and moisture in the microwave. These waveguide covers are very easy to replace from inside the oven cavity. Touch up any paint that may have chipped or come off because of the arcing.
If your waveguide cover and/or stirrer are all OK, then the spark is coming from your magnetron. The antenna on your magnetrom has overheated and burned, sending the microwaves out at the wrong angle. If you catch this microwave oven repair early enough, you can usually get by with just replacing the magnetron. If the arcing has caused servere damage inside the waveguide, you will need a new microwave. Waveguides are not replaceable and most you can barely see into them, let alone sand and re-paint. In this case of microwave oven repair, when you remove the magnetron, you will see the burned antenna, or your magnetron will fail the test bel

it may be repairable but not by yourself
take it in for a quote and proper diagnosis

Presuming that you have iliminated the possibility of any metal objects that are not meant to be in the machine being in there (and this includes dishes and other items with silver or gold leaf on them, which WILL spark and burn!) then take a look inside the oven its self. You will find a waveguide cover. It is usually a strange flakey silvery plastic/card like material called Mica and is usually on the same side of the microwave wall as the control panel (So if the picture on this thread is accurate, I will guess the Mica cover is on the right hand wall inside as you look at the machine from the front) . Over time, the magnatron (the thing that creates the microwave energy) will often burn a hole through the mika, or cause a dark brown or black burn mark in it. If this cover is even slightly damaged then it may well cause sparking inside the machine. These covers are designed to be removed and you can buy replacements for them from electrical stores.

Hi, a mica cover is inside the oven cavity, usually on the right hand side or in the roof you will usually see a small cover that looks like it is made of cardboard. It is often held in by one or more screws. It is called the waveguide cover. It is usually made of a material called Mica. Its purpose is to cover the aperture through which the microwaves enter the oven cavity from where they are produced by the Magnetron behind the control panel. It stops moisture and food particles getting into the "workings" of the microwave.

That "Cardboard" item is a wave guide cover and is critical part of the machine.
It is made of mica and needs replacing. The magnetron is OK as long as it does not spark too much or get any foreign items in there.
Replace the wave guide cover.

No the wave guide is usually a porous material that almost looks like a light colored cardboard piece. Sound as if the stirrer plate is waht you are seeing. Make sure M/W is clean inside completly. Any build up of grease can cause this. Also make sure to check for chipped areas and if there are use an appliance touch up to cover the bare metal areas. A good cleaning will usually take care of the arcing tho.

you need to replace the cavity cover "the cardboard like",the antenna bearing set "the gun barrel like" and the gear motor.If the "gun barrel like" is stuck up because the gear motor is not rotating excessive heat will occur inside the microwave thus burning the cavity cover.

The cover is probably the magenetron. That is where the microwaves come from. If the bread was moist, it might have left condensate in the unit which is causing the sparking. Unplug the unit, leave the door open over night. If you can remove that cover, do so. Be sure to carefully replace it before using the unit. Never turn on a microwave with nothing in it.