My 89 L98 GTA has had a pretty good oil leak since last year. Went through a quart in 200 miles This whole time i thought it was my intake or distributor seal. Noticed recently that there was even some spatter patterns on the firewall

upon further inspection and using oil dye, it seemed that there was a lot of dye around this plug that is on the top rear of the engine block. a buddy of mine has an 88 GTA and said that's where his oil sender is. however mine is located on the bottom by the oil filter

So do these commonly leak? it would make sense with it being under a lot of pressure and whatnot.

It's exposed to what ever oil pressure the engine normally produces. I'd take out the plug and make sure it's not cross threaded. Clean the threads, apply some Teflon pipe thread tape, put it back in tight but not overtight. Don't want to strip the threads

Is there a tool you recommend to remove it? I'm trying to do this without having to remove the lower intake..

I don't know for sure without seeing the plug. Mine has the sender unit in that spot, which I recently changed with just a wrench, didn't have to any intake parts off.

If it has the factory plug you need a little 8pt socket.

These can be problematic with leaking, the factory oil sensors on the small block engines often end up with an oil trail all the way down the bell housing. Like Lonestar7 said, teflon tape it and reinstall or get a slightly longer plug from a hardware store for more thread contact and use 4 to 5 wraps of teflon.

I have the same problem did u ever fix your leak? I took my plug out which had a square end on it Teflon taped it and put it back in and it still leaks a little when revving engine. Is the square plug the original plug? Should I try a longer plug?

I just wrapped a lot of Teflon tape around the threads and then got it nice and tight. Still in the process of putting it back together. I'm not liking that you said it still leaks after you did that lol

does your plug look like this?

Very similar yes

Maybe I should put more tape on it. Did you remove the dizzy to get it out? I am going to take it out again and try to fine a better plug. I really thought I had it fixed did not leak for a couple days tell I started to beat on it then it started to leaking slowly.

Yep I found that removing the dizzy made things easier. Try more tape and see if that works. Did you use a 9/32 wrench to take the plug out?

I used a 7mm wrench it was a super tight fit did not want to strip it. lol

I really just don't get how it would leak even without the Teflon tape the plug was super tight to begin with.

Yea mine was tight too. I really hope it fixes it cause the *** of my car is covered in oil lol

the last time you changed your oil did u add any oil additive like stp or lucas ?

Nah. I feel weird putting anything other than oil in there.

A 8pt socket set is what you need for this. Be very careful on how tight you go with it because the back of the china wall can break off if its to tight.
Maybe thats whats going on, a small crack in the wall. Hope not!!!

I hope not too. I've never messed with it til now so I really hope there's no crack

Got everything back together and didn't fix the leak one bit

Sounds more like a china wall leak.

I suppose there's no way to fix that other than a new block huh

Just R&R the manifold and redo the RTV.

Did that 6 months ago. Plus the oil is coming out too quick IMO to be an intake leak. There was some oil spray on the firewall too. It's gotta be something under pressure

Have you actually seen any oil leaking with the engine running? Have someone rev it while you watch the area where you think the leak is with a bright flashlight. I wonder if it could be leaking somewhere around the dizzy shaft?

I put some oil dye in there and used a UV light and that's where most of the uv light showed up