Dryer door pops open. leaves burn marks on clothes.

Gas Dryer no heat: or shuts down soon after heating CHECK:

Thermal Fuse
If the air flow in the dryer is restricted, the temperature in the heating chamber can get hot enough to blow the thermal fuse. If the fuse blows, it cuts power to the coils that control the gas valve. The fuse is usually mounted to the exhaust duct just inside the back panel. You can check its continuity with an ohmmeter. If, after disconnecting the fuse, you get any reading other than 0 when you touch the leads of the meter to its terminals, it has blown. There's no way to restore it -- you'll have to install a replacement.

Igniter and Gas Valve Coils
TEST with a multi meter: The igniter is an electric conductor that works like the element in an electric heater, glowing hot enough to ignite gas when you turn on the dryer. This conductor can burn out, and when it does, it may glow, but it won't get hot enough to ignite the gas. At times it may give a reading of continuity yet fail mechanically and not get hot enough to ignite flame though it gets hot and glows and even may show Ohms or continuity ( close circuit) ?
Occasionally, the Gas safety valve and the electric coils that control the gas valve are defective -- they can wear out when the dryer gets old. When this happens, the igniter glows, but gas never enters the heating chamber or does not stay consistant.
Performing a continuity test on either part will help you determine whether or not you need to replace it. But the coils should also be tested for amount of resistance as well as Ohms. As they may be showing ohms yet not putting out enough resistance to keep proper gas pressure flowing. Most coils should show at least 1300 ohms ( GIVE OR TAKE 150 OHMS). Anything significantly less Thus u get an ignition but then it soon goes back out. The flame does not stay lit.

Air Flow and Heat
The motor that drives the tumbler also drives a fan that circulates air through the heating chamber and the tumbler and expels it through the vent. If the air can't circulate, perhaps because of lint blockage, the heating chamber overheats, which prompts the cycling thermostat to turn off the gas. The thermostat resets when the chamber cools, but the chamber heats up quickly and the thermostat again shuts off the gas. The result is that the temperature in the tumbler doesn't stay hot, and your clothes take longer to dry, if they get dry at all.

Warning
There's a big difference between a dryer that doesn't heat up at all and one that just doesn't get hot enough to dry your clothes. In the first instance, the problem is usually a defective part, and things should be back to normal after you replace it. In the second instance, the problem is caused by restricted air flow, and you need to clear the lint filter and vents and take steps to prevent lint build-up. If you don't, you'll use more energy for drying than you need and the dryer may continue to malfunction. Worse, you may have a dryer fire.

these newer dryers are such garbage with their thin Sheet metal. see if the door is bent by the hinges. Dropping clothes on the doors bend these newer machines. then they don't seat correctly

if it works on auto but not on time you have a bad timer,it's not counting down,it's better to use auto anyway,when the clothes dry the dryer shuts off on it's own,this way your not using extra electricity,if your clothes dry in 30 minutes and it's on 60 minutes it will still run after the clothes are dry on auto it doesn't.if you open the door and look around the opening you'll see a tag with the model number,your missing a couple of letters on the model number.

We had the same problem and surprised how rampant the issue was after referring to the internet reviews / troubleshooting, etc. The problem started after about 6 months and the solution came to me after much "headaching" over the problem. There were no 'codes' coming up just the door popping open during the cycle. I purchased a (2) twenty pack of 1/2" diamerter x 1/16" thick N42 Neo Earth Magnets and placed them along the top edge and bottom edge of the dryer opening. Instant fix in less than a minute. The thickness does not interfere with the door opening and the strength of the magnets is obvious. Hope this helps. Fix was less than $10 bucks and no service man, etc.

Try putting less of a load in dryer. The weight of the clothes riding against the door, may be the reason why it pops open.

There are many different door latches, Most of them are 2 pices, the part on the dryer door and the reciver on the frame. Most of them come in a kit with both pices. you will need the model number to get the part numer when calling.

stat or a clogged vent system. Clean any lint from the internal and external ductwork, and/or replace the cycling thermostat (read about cycling thermostats in "Drying is too slow," above).
Drying is too slow It normally takes about 45 minutes for a dryer to dry a full load. If your dryer is taking more than an hour, check these.

Vent
Heating element
Internal ductwork
Cycling thermostat
Vent Frequently there's an obstruction in the vent duct from the dryer to the outside of the house. For the dryer to heat properly, the duct must be clean and clear of lint or any other substance. 

Heating element Your dryer's heating element may be partially burned out. If it is, your dryer still heats, but at such a low temperature that it takes three or four times as long to dry the clothes. If the element is partially burned out, replace it. 

Internal ductwork Your dryer has some internal ductwork. If it gets clogged, your dryer can't dry properly. In most dryers, to get to the internal ductwork to clear the clog, you have to substantially disassemble the dryer. A quick way to check for internal clogs is to remove the lint filter and use a flashlight to inspect the inside of the duct. If it looks clogged and you can't clear it using your vacuum, contact a qualified appliance repair technician.

Cycling thermostat Although this isn't a common problem, one of the thermostats that controls the temperature in your dryer may break and cause the dryer to heat poorly. If so, you need to replace it. The thermostat is usually a small, round, black device mounted to an oblong steel plate. The plate is mounted to the internal ductwork with two screws.

Chances are the little plastic latch keep is broken. Look at the door and locate a peice that will press into the front area where the clothes go in.
Once you see it, check the keeper and see if it is broken. The door should not just pop open.

It sounds like a timer problem since it happens during timed also. Some dryers don't have an actual moisture sensor for auto dry. They work by knowing that as long as the clothes are wet the temp won't go past a certain point. As the clothes dry it trips a thermostat that lets the timer advance. Until this is fixed DON"T trust the timer to shut off the dryer. Sometimes it won't or could leave the dryer running for hours. This has nothing whatsoever to do with fuses. There are no fuses in a dryer. Just high limit thermostats and other devices that will shut off the heat but usually not the motor.

throw a clean pair of old sneakers in the dryer with the clothes. this should not allow the clothes to stay in one place during the entire dry cycle