Not sure you will get a reply from the OP as that post is from 11 yrs ago.

I am not a knowledgeable repair person so take the following as just an opinion - To me for the air to pulsate the blower fan would have to be changing speed either due to the voltage varying to the motor or the fan slipping on the drive shaft. On my drying the drive shaft is D shaped and the slipping happens due to the fan being cracked where it slips over the shaft.

exhaust air pulsates. the length of the pulsate varies greatly. seems to blow hot. was noticing this pulsating noise when i went to bed. the next mornig nothing worked. turned out to that plug in wall had shorted out and did NOT trip the breaker. I replaced the outlet and the pulsating continues. I have the vent disconected from the wall and can feel the exhaust pulsating. What is getting ready to go out? Did a bad connection in the outlet cause the problem or did the problem cause the outlet to go bad? I can not afford to replace the dryer let alone burn my house down! Lint also goes around filter alot. have used shop vac to clean out behind filter and down exhaust shield. lot of lint catchs at edges of lint trap.

Fridgidaire LER331DSO electric dryer