Posted recently was a problem with a crank sensor.
I'm doing 178K mile maintenance on my '95 2.0L <grin> Pulling every nut and bolt I can, while doing a clutch.
The crank sensor mounts in a pot metal adapter, bolted to the block from the trans side. Corrosion pushed the adapter slightly out of square with the rear face of the block.
In my case not very much. But I pulled it and cleaned and greased the heck out of it.
I'm doing a rear seal as well, but not pulling the seal adapter. I removed, one at a time, the seal adapter's mounting bolts and Loctited them. One of the bolts wasn't as tight as I would have liked to find it.
The oil stripper/ where the PCV valve is located, weighed 3 or 4 lbs. The cat does a nice job of baking it full of crud.
The bolt holding the pot metal adapter can easily be overtightened since I used an RTV type sealant. So I safety wired it.