Sewer ejector pump smells

I have a sewer ejector pump that was installed in my basement from the previous homeowner who but a shower, sink and toilet in when he finished the basement. I have noticed periodically that the basement will get a sewer like smell only in the area where the pump is. I noticed that the vent from the pump is capped off with an autovent..he did not run a vent pipe to the outside or through the roof. Can this be causing the smell and is this acceptable under code? If not, how can I find solution to this problem?

Thanks,

The basin needs to be vented up and out, and an AAV would do nothing good in this type of set-up. This should be addressed ASAP as sewer gas can be highly poisonous.

The local building inspector might allow venting out a sidewall, but I believe most locations would specify venting out through the roof.