It takes 25 minutes for my oven to preheat and after 30 minutes the internal temp of any thing is only about 155 degrees. Whill it is preheating the flame will go on and off.
Answer Hello Rocky. Test for 3.2-3.6 volts AC at the gas safety valve with the igniter turned on. If the voltage is there, you have a bad safety valve. If the voltage is low, you have a weak igniter and the igniter will need to be replaced. You can test this with a multi-meter TJMA-DMT3. Here is a link on how to use a multi-meter. http://forum.appliancepartspros.com/oven-repair-including-ranges-cooktops/4810-how-check-continuity-ohmmeter.html
Oven ignites with good flame for a few seconds then goes out and comes back on with small flame.
Answer Hello Joe. That sounds like a pressure regulator or gas valve issue, if the flame is to small to heat properly.
Oven Op Panel shows correct temp, but actual temp is much lower. Checked resistance on temp sensor, it was 1107 ohms at ~70 degrees. It appears correct. What else could be wrong?
The oven sensor should be at 1090 ohms plus or minus 10 percent at 77 degrees. If the sensor is checking ok then you would want to check the wiring from the sensor to the control. If wiring checks ok then you will want to check the elements to ensure that they are getting proper power and check to make sure that neither of the elements are bad.
My pilot light is on in the oven but the oven will not come on. What part to I probably need.
Answer BF, Under the circumstances, You most likely have a weak oven igniter 12400035, it's a bit hard to tell without a proper model number. The igniter can glow but not produce enough amperage to open the oven safety valve. You should be able to remove the oven bottom panel, turn on the oven and observe if the glow bar igniter glows "white hot" and produces the 3.2 to 3.6 amps needed to open the safety valve.