I have a GE Profile built in Oven , model # JTP11WS2WG. It has worked great but now, when set to "Bake" it will not get up to temperature. Usually about 100 degrees less for 350 and the higher the setting, the greater the difference. If I set it on the highest bake temp, it will get to 550 degrees. It cleans and the broiler seems to work fine. I adjusted the temp up 35 degrees but it only made about a 100 degree difference. The unit is 17 years old and the oonly parts I seem to be able to find are "generic".

I mis-typed. It should say 10 degrees difference, not 100 degrees difference.