1998 yukon, is my intake manifold really bad at all?

[OilBurner2003]

Hello everyone! Back here again with more confusion than ever before. I've been chasing this oil leak for a while, and a lot of the folks have directed me to the Intake Manifold gasket, and that it could be leaking oil. However, I'm not too certain this is the cause anymore. What's in the picture is behind the passenger side exhaust manifold. I know it's hard to see, but...Where is that oil coming from? I've just noticed it. In fact, when I look behind the exhaust manifold farther past that spot towards the rear of engine, my entire side is SOAKED! in oil. But it's a very small drip, so what the heck is down there, and what am I missing? Is this possible it could be coming from the intake manifold gasket? The second pic is right below the rear main seal, (yikes) But I can't confirm it's this seal without finding out what the heck is coming out of the front. So... It's a weird situation. It's not the pan or lines, those were done by a mechanic. I think I have one more trouble shooting spree left in me before it goes to a mechanic, because I'm stumped. Remember, In total: Oil leaking from back of engine, Oil below passenger side exhaust manifold, oil on bell housing, oil on pan, and oil below rear main seal. It's too much for me to narrow down. Unless the intake manifold can cause ALL of that, looks like it's going to a shop. Thank you for taking the time to read this disaster of a situation!

 

[wjburken]

Hello everyone! Back here again with more confusion than ever before. I've been chasing this oil leak for a while, and a lot of the folks have directed me to the Intake Manifold gasket, and that it could be leaking oil. However, I'm not too certain this is the cause anymore. What's in the picture is behind the passenger side exhaust manifold. I know it's hard to see, but...Where is that oil coming from? I've just noticed it. In fact, when I look behind the exhaust manifold farther past that spot towards the rear of engine, my entire side is SOAKED! in oil. But it's a very small drip, so what the heck is down there, and what am I missing? Is this possible it could be coming from the intake manifold gasket? The second pic is right below the rear main seal, (yikes) But I can't confirm it's this seal without finding out what the heck is coming out of the front. So... It's a weird situation. It's not the pan or lines, those were done by a mechanic. I think I have one more trouble shooting spree left in me before it goes to a mechanic, because I'm stumped. Remember, In total: Oil leaking from back of engine, Oil below passenger side exhaust manifold, oil on bell housing, oil on pan, and oil below rear main seal. It's too much for me to narrow down. Unless the intake manifold can cause ALL of that, looks like it's going to a shop. Thank you for taking the time to read this disaster of a situation!

Have you checked your valve cover gaskets?

 

[OilBurner2003]

Have you checked your valve cover gaskets?

Both valve cover gaskets have been replaced and are not leaking.

 

[wjburken]

Both valve cover gaskets have been replaced and are not leaking.

I am not aware of any oil passages that would put enough oil into the intake manifold for it to leak oil based on having to replace the lower intake gasket on my 1997 K1500 earlier this year, but I am not a expert. Not trying to be a smart a$$c but are you sure it’s oil? Those are more likely to leak coolant than anything else.

 

[OilBurner2003]

I am not aware of any oil passages that would put enough oil into the intake manifold for it to leak oil based on having to replace the lower intake gasket on my 1997 K1500 earlier this year, but I am not a expert. Not trying to be a smart a$$c but are you sure it’s oil? Those are more likely to leak coolant than anything else.

It is absolutely oil. And I’m wondering the same thing too, I don’t have a lot of evidence that says a intake gaskets can do this, so that just eliminates one factor. I hope!

 

[OR VietVet]

Definitely looks like a rear main seal but you also have another leak. The rear main will not leak upstream.

The way to absolutely pin it down is to power wash the affected areas completely and add dye to the oil and then have a look see after one drive, two drives, three drives...whatever it takes.

 

[OilBurner2003]

Definitely looks like a rear main seal but you also have another leak. The rear main will not leak upstream.

The way to absolutely pin it down is to power wash the affected areas completely and add dye to the oil and then have a look see after one drive, two drives, three drives...whatever it takes.

Yeah, I explained in other posts oil isn’t gonna travel upstream. Thank you for the input! I will do that.

 

[OR VietVet]

I do suspect it is the intake though or the possibility of the seal at the distributor.

 

[OilBurner2003]

I do suspect it is the intake though or the possibility of the seal at the distributor.

I've always had a hard time understanding that seal. What is it again? It's the part that goes down in the block, right?

 

[OR VietVet]

Is an o-ring on the shaft of the distributor