Kitchen Gas Appliances - Maytag gas over reads wrong temp

RE: Maytag CRG9700 Gas range.
I set the oven temp to 400 degrees. When the control beeped, the indicator read 400, but it was definitely not that. I measured with an external thermocouple and the temp was actually 220 degrees. I raised the set point of the controller to 550, and after the indicator read 550, I measured the the temp with the external TC and found it to be in the range of 330-350.
I recalibrated the controller to the +35 degree max and the temp of the oven went up to over 500 (measured by the external TC). I lowered the oven set point to 400 and the TC measured temp dropped to 250.
There is no smell of raw gas now like there was before I replaced the ingnitor a couple of years ago.
I'm not sure whether the problem is the sensor or the control module. Please advise. Thanks

Update on oven temp. The sensor checks out at 1060 ohms. I noticed when I set the temp at 400 degrees. When the oven temp is indicated it shows 250 degrees even though the actual temp is room temp. This would suggest to me that the reference thermocouple in the controller is off, or the the related circuitry has deteriorated. I don't see any apparent means of calibrating the reference circuit. The calibration procedure will offset the error, but is limited to +/- 35 degrees.
Unless there is something that I am overlooking, it looks like the controller shot, which means that I will need to replace the stove. since the chance of my finding another controller is nil.

Sorry about your oven troubles. I had the opposite, mine would say it was at 350 when in reality it was 600. I also ran into the 35 degree barrier.

You can get new controller, mine listed at almost $200. It was easier to replace the stove instead. Just do a search on appliance parts and have your model number ready.

Hello timoch. Welcome to Gas Appliances topic and our Do-It-Yourself Web Site.

Care to advise what condition and/or problem caused you to begin checking the ovens temperature? Was the oven burning or under baking any food items? Which would prompt you to begin the temp and ohm checking? Calibrating checking, etc.

Based upon the temps indicated by the external meter, the ovens temp should be under baking all food items. If so, advise. Knowing why you began checking often helps determine a possible cause more so then checking temps etc.

Have you inquired as to what the most common and or likely causes are from your local appliance parts retail store person. They are likely to also know and provide the possible solution(s). Often worth a try imo....:)

The first hint was when I set the temp at 400 degrees to bake a frozen pizza, and when I checked it after 25 minutes it was still raw. I have a multi VOM tester which came with a thermocouple so I used it to measure the actual temp which was about 225. Oddly enough, when I cranked the control up to 550 degrees, the actual temp went up to 550 degrees, but when I lowered setting on the controller at all, the actual temp started drifting down until there was a 175 degree error.
I located a supplier who has a new controller, but at a price of $285 +s&h. I can get a good newer used stove for less, so unless I can find a way to repair the circuit boards in the controller, it's scrap city for the old stove.

Thanks for the help anyway.

Ps... Cooking the pizza at 550 degrees gave me the best pizza that I have ever baked.

Thought you might like to know what I found. I asked my son the engineer and he said it was most likely bad electrolytic capacitors in the circuit board of the temperature controller. Sure enough, when we examined the board, there were two leaking caps... we replaced them at a cost of $1.00, and now it works. :):)

That was a good find. Good work.

Maytag MGR5875QDQ
It initially heats to the correct temperature, and then when restoring heat, it exceeds the temperature by 53F. The easy solution is to set the temperature lower by 47F. However, DW is concerned it will not be reliable.
Would looking for bad caps be advised or should we just wait for total unreliability?