Sry to ask a stupid question on my first post but here it goes. I just bought a 91 z28 off of ebay and when it came and was leaking oil. After about 3 days I got it home and there was absolutely none left. I filled it back up and it's not leaking anymore. It was leaking in puddles on the backside of the motor. Don't know if anyone has heard of this figured I'd give it a shot.

 

really weird for it to suddenly stop leaking....


Not uncommon for a 15+ year old motor to be leaking through all or any gaskets though!

 

mayb the guy used synthetic oil like Royal Purple, that stuff usually blows through seals because of regular oil depositing on the seals and protecting them, but the synthetic ones will wash that depositing away and leak oil. did you fill it back up with a regular oil?

 

Yes sir, I filled it back with some standard valvoline 5w-30. Yeah i couldn't tell if it was leakin while running but I do know it leak while just sittin in my garage. It's been day two and not a drop on the floor.

 

whats the dip stick say though

 

Nm, I let it idle for about 5 mins just now and theres about an inch puddle of oil. Maybe I didn't idle enough last time I looked at it? Anyways I'm gonna take it to the shop tommorow have them look at it. Thanks again. I thought that was to wierd to be true.

 

I went ahead and bought a set of ramps and looked myself. It's coming from the oil pressure sensor. I'm sure the steps would be 1. buy new oil pressure sensor. 2. drain oil 3 install sensor 4. fill back with oil ??? I did a search for oil leak and seen a couple for that oil pressure so that's what lead me to look there. Just don't think any install directions were there (if so sorry) I just wanted to make sure before I tackled it. Thanks

 

No need for the drain & refill. Just change it out.

 

Yea, it's at a high point, so it doesn't really leak from there while you're changing it (as long as the motors not running!).

Get some teflon thread sealant, and put it on the threads of your new oil pressure sensor to make sure it won't leak again. Hopefully thats your only leak.

 

Ok. I'm about to give up. When it's idling it doesn't leak at all. When I'm driving it is when it must happen because I look under the car when I'm stopped and I can see it leaking. Also it's not the oil pressure sensor I can see it now coming from right beside it coming down. So I'm guessing from a valve cover, but I would have thought it would of dripped on the headers. I'll let ya know what I find out. I also put some oil leak stop additive so I'll see if that was worth the money. Thanks again.

 

So, is it down low on the right side?

Has the smog pump been hacked off of the car?

 

Possible leak between the intake and block on the backside. All of my sb Chevy's have had this problem at some point. Run your fingers along the backside and check for fresh oil.