Ok noticed my '89 Festiva leaking oil and was doing it kinda rapidly. Figured it must be rear main. Removed transaxle and replaced seal and clutch while I had thing apart. Oil pressure since I've got it is when hot around 50psi driving down the road and between 20 and 25 sitting at idle. Ok next day I am travelling. When I stop to get gas, I am down over a quart and oil everywhere. Cant see where its coming from. Well went through maybe 6 quart in a 750 mile drive. Underside of car is a big oil slick. People think car is overheating when I am at an idling stop or when I first park because of oil vapor raising from around hood. Someone says they see oil dripping from around mechanical fuel pump (kinda buried on firewall side of head). Ok, reseal that with the 15min wally world putty epoxy since I would have to special order spacer and gaskets for this pump and dont have time for that. No more oil leak from around fuel pump. On way home use maybe 3 quart, but weird the oil pressure at hiway speed is dropping. Starts at 50, then 45, by time I was close to home down around 35, but still over 20 at idle (it should drop also with a leak/bad bearing or so I would think--I checked oil level often just to be sure it wasnt that). Get to thinking maybe its the little copper line from block to oil pressure gauge. Ok today I put it up on jack stands and since figure it has to be either that or oil filter, I replace oil filter while engine is cold. Start it, let it get to operating temp. Crawl under with it running. Not a drop oozing, leaking, or otherwise coming from engine can I see nor the copper line to the pressure gauge. Get in drivers seat to turn it off and notice its idling at 30psi (in range of what manual says one of these engines in good condition is supposed to). Rev it and it hits 60+psi (thats really good), let up and goes back to 30. This is a fully warmed up engine. Ok, could a faulty or plugged up oil filter cause this condition. Thats all I changed. I guess all oil could be from around oil filter gasket or pinhole in the filter. Know for sure when I take it on hiway again. See if oil is still thrown all over. If I am still getting an oil slick, dont know quite where to look next.