Generic Electronic Module. It is basically what controls everything electrical that the PCM (Powertrain Control Module) doesn't (except ABS and PATS). Before the GEM, you had the Central Timer Module and Central Locking Module that did pretty much the same job. It sits next to the PCM behind the glove box.maybe a newb question but what's a GEM?
what do you mean by holding the little door open?Spray the inside of the lock with electrical contact or MAF cleaner; make sure to hold the little door open so the gunk comes out. Give it a minute to dry, then spray a dry lubricant in the lock like graphite or Triflow.