We know the distributor O-ring is a bad source of leaks as they harden with age and crack.
Unfortunately, when you ask for a Fiero distributor O-ring, you get the same crap Buna-N black O-ring.
What you want is the better tan colored Viton O-ring which stands up to engine heat better.
The problem is the parts guy can't find the thing "for the Fiero".
Later year V6 engines with DIS systems didn't have a distributor, but they still had a geared drive
in the distributor's place to drive the oil pump. These later applications have the Viton O-ring available.What you need to ask for the the O-ring for the Oil Pump Drive Gear.
Sometimes they call it a Seal and maybe Oil Pump Gasket (see example)
This example is for a 2004 Grand AM with the 3.4L (3400) engine.
ACDELCO Part # 10477565 http://www.rockauto.com/cat...426698,parttype,5444
Fel-Pro Part # 704841 http://www.napaonline.com/C...FPG704841_0147537476
NAPA's Part # is 655-1294. http://www.napaonline.com/C...DP6551294_0374155317
I think you may find them in "Help" packages as well.
Dorman PN 90441 - Distributor O-Ring Assortment
For "insurance" I also use a Felpro distributor base gasket (thanks for the pic Schurkey)
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[This message has been edited by fierosound (edited 11-11-2020).]