nrs2420

iTrader: (2)

Yesterday my 98 SS started leaking oil. There was a pretty good spot of oil under the car. So I jacked it up and noticed the whole bottom of the transmission covered in oil. It's coming down the passenger side of the car from the back top of the engine. The head looks like it has very little oil on it (mostly just looks like it seeped up a half inch or so from the bottom of the head). It looks to be coming from the intake manifold area (very hard to tell though). After doing searches it seems like I don't see much on the LS1 intake leaking (found all kinds on the LT1 leaking though), but found it may be the oil pressure sending unit. My question is does this sound right and how do I check the sensor without taking the whole manifold off?

davidws6

iTrader: (36)

The intake won't leak oil as there's no oil under it or around it. Other then possibly the engine ingesting oil from the PCV.

Probably your Oil Press Unit.

On a 98 / 02 F body, really no way to C it unless you pull the intake !

Not really much of a PITFA. Just clean if off good B 4 U pull it.

nrs2420

iTrader: (2)

That's what I figured, thanks for the tip

nrs2420

iTrader: (2)

Is throttle body cleaner the best thing to use to clean up the top of the engine? I don't want to screw any stuff up.

Also do I need to buy a new sensor or is there a gasket that I can replace? Do I need to buy the OPSU socket?

doubleD_white_t/a

iTrader: (1)

the oil pressure sending unit is on the driver's side isn't it?

Hemi2Slo

Yeah it is. OP, if your leak is on the passenger side of the car you might want to check the valve cover gaskets. My truck has a leak in its valve cover and it runs down the passenger side, its not nearly as bad as you described yours to be but it is present, and you cannot see it on the head. I've also heard of other LS engines leaking in that way.

nrs2420

iTrader: (2)

Well as far as I can tell it's not the oil pressure sending unit. I can run my hand all over where the OPSU hits the block and there is nothing. Is it possible it could be the valley cover leaking?

I also have my oil pan gasket leaking, I don't think it could get on top of the bell housing, could it?

Guess my next step is taking the intake manifold off to get a closer look. That will have to wait till this weekend.

nrs2420

iTrader: (2)

Ok so I had some time and I took off the intake. This is what I found



Do you think the Valley cover is leaking or is my rear knock sensor leaking?

I plan on doing the upgrade knock sensors with a new harness and I go ahead and do a new valley cover gasket. I might as well do the oil pressure sending unit since I have it off although I don't see anything around it.

Also the connection for the three PCV lines in the back was broke, so I'm going to get some 3/8 fuel line and a t-connection and redo the PCV lines and go ahead and get a new PCV valve.

Anything else I should do while I'm in here?

MJs1FastSS

iTrader: (149)

yeah you can make a new PVC connection for very cheap and not buy a new gm pvc line as they are over 100 $ but where your there clean all that on top of the valley cover and your ports with a vacum to get the years of grime off.
Personally i would replace the valley gasket as well as the knock senors just to ensure it's not that while the intake is off
if the OPSU isnt leaking i wouldnt replace it just be care when you put your intake back on

CHRRRIS

Did you ever figure out what was causing the leak?

nrs2420

iTrader: (2)

Honestly I think it was my valley cover, but I'm not 100% sure because I replaced that, the oil pressure sending unit, and I upgraded to the 99+ knock sensors and put new grommets at the base of the knock sensor holes. All I know is it's not leaking at this point so I'm happy.

CHRRRIS

Haha right on. Did you replace the valley cover itself or just the gasket?

nrs2420

iTrader: (2)

Just the gasket

masterz28

iTrader: (8)

Thats good, my tranny pan is satrting to get covered in oil, oh damn...

JL ws-6

iTrader: (50)

God damn.. I sometimes forget how old these cars are getting.... but every now and then I see a picture like that and it reminds me!

Good work on finding the leak.... but from now on I'm giving you a homework assignment... clean that car, and alot more often

nrs2420

iTrader: (2)

lol, yep she's going on 13 years old. I do feel bad because I don't have the time I use to to keep up with the cleaning.

Schantin

iTrader: (6)

Just found this thread.....and am very glad you posted the pic. My heads/valley cover looked exactly the same when I pulled the intake yesterday searching for a leak as described.

I just about crapped an entire litter of kittens when I saw the sludge in my head ports. Seeing your pic made me feel better At least I know what the problem is now. Was envisioning the worst when I saw the gunk!