Hi, this is my first post, so not exactly sure what to do. I have a 2001 monte carlo LS with a 3.4 motor. I have antifreeze getting into my oil and am hoping that its a leaking intake manifold gasket and not a head gasket leak. Is there anyway to tell where my antifreeze is entering the motor without taking it to a shop? Please help as I do not have much money.

 

99.2% sure it's the L.I.M. gasket

out of all the 3.x liter engines i've had and worked on, it was always the manifold

try pulling 1 spark plug at a time and cranking the engine over to see what cylinder(s) it's leaking into

is it running rough?

 

It is running great. I noticed it running hot the other day for the first time; checked antifreeze in radiator and it was low so I filled it up and the car was no longer running hot. I then checked the oil and noticed it was brown and milky and about 2 inches above the full mark.

 

It most likely is te LIM gasket. Not really hard to change out.

 

Is there anyway to tell before digging into it whether or not it is the LIM gasket

 

Thanks Jimbo7 and DRuben for replying!!

 

Im not sure... I looked under my oil cap and took the top piece off and saw milky stuff. After I cleaned it and changed the gasket it never reappeared... I guess you can check the oil cap... Also, While changing the lower you might as well change the upper because it has to come off anyways. Make sure you change your oil if you do have coolant in it!

 

Thanks so much for the information. I will change the oil after replacing IM gaskets. I also plan on flushing the radiator.

 

Sounds good . I believe there is an aluminum gasket for the LIM that isnt prone to breaking like the cheap factory gaskets. It definately would be worth getting unless you like counting how many times you can take your motor apart and have it still work like me

 

The coolant ports of the LIM in the 3400/3100 are the outside ports of the gasket. If you loan-a-tool from the auto parts store of a radiator pressure tester and bump the pressure to what the radiator cap says is max (or just a little under), odds are you will see coolant bubbling out of where the LIM and the heads meet. That is your 100% answer.
BUT, having traces of coolant in your oil is a fairly good sign of the LIM gasket failure. It's not often it's a head gasket.

FelPro makes the aluminum LIM gaskets ones. Order them from RockAuto (rock is a sponsor of MCF, they have posted a coupon code, save extra $$$ in the process).