Here are some of the possible sources of an oil leak on a 1991 Toyota Camry:
* Valve cover gasket
* Oil pan gasket
* Timing cover gasket
* Rear main seal
* Oil filter housing gasket
* Distributor cap gasket
* Spark plug tube seals
If you find that the oil leak is coming from the distributor cap, you should replace the cap and gasket. You should also inspect the distributor for any other damage, such as a cracked housing or worn bearings. If you find any damage to the distributor, you should replace it.