Dryer not heating enough after replacing heat element

Kenmore Dryer Model #6091 (?)
Just replaced the heater element a week ago. Now it heats, but not very much. It takes 2+ hours to dry a load and by then the clothes smell sour. When I looked Up troubleshooting it said that one of several Thermostats might be out. How do I know which one to replace, or do I replace them all? And is there some way to Know if this is actually what’s wrong with it?
[COLOR=black][FONT=Arial]Thanks
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Your model number is incomplete.
Kenmore/Sears numbers are usually 3 digits, a period and then an additional 8 digits.
Please check it.
http://www.appliancepartspros.com/modelnumber_locator.aspx

Why did you replace the heater?
Your posts suggests that you had no heat at all but does not actually say that.

How do I know which one to replace, or do I replace them all? And is there some way to Know if this is actually what’s wrong with it?
Yes but we need a model number and then with luck we can find the wiring diagram for this unit. You can then troubleshoot the unit.

I would try the following first.
Poor venting is the most common cause of poor drying.

Unplug the unit and disconnect it from the vent system.
Now try a run.
If it now dries OK odds are the vent system needs checking/cleaning.
Be sure to check that the louvers on the outside of the house open correctly.

If you do not want any lint in the house.
Take a pair of pantyhose.
Put one leg into the other and then attach this to the dryer’s vent.
Leave enough room so the pantyhose can balloon out like a windsock.

Both the above will let you check the temperature and the air flow.

Note: The above is not recommended for gas dryers due to carbon monoxide concerns.

Sorry 'bout that -
Model number 110.60901990
I had no heat at all a few weeks ago. So I replaced the heating element. Now it just gets warm, not hot.
The venting is good. I even replaced the venting to be sure, and checked the air flow outside. It was blowing plenty of slightly warm air.
I have the wiring diagram and all the other diagrams. If you want I can scan and send to you.

Thanks

Check the cycling thermostat on the blower housing next to the thermal fuse that typically would be the problem…it should be 4 prong…2 prongs ohm test at infinity and the other one has low resistance…continuity test this i bet it’s your problem…even sometimes when they test good they get loose inside shake it see if it rattles…here’s your part:
http://www.appliancepartspros.com/whirlpool-dryer-cycle-thermostat-8318268-ap3045874.html