I'm afraid so. GM V6 and V8 engines of that era had trouble with the plastic intake manifolds cracking at the web and with the lower intake manifold gaskets dissolving in the Dexcool coolant GM mandated. See the sources. The lawsuit was completed and the window for claims has closed. The engine must not be run until it is repaired... around $800 parts and labor. Modern gaskets are impervious to Dexcool.

Look at it this way: Ford cars and trucks have lost more plastic intake intake manifolds than all manufactures COMBINED.

Apparently manufacturers save pennies by having them made of plastic rather than aluminum. Newer Impalas no longer have plastic intake manifolds.

I have a 99 Grand Prix which has a motor exactly like yours. It's never overheated, cracked the intake or lost an intake gasket.

Yep, the 3.8L (series II) has this problem because the heat from the EGR causes the intake to crack and dump coolant into the intake ports, look right under the throttle body and if you see coolant this is your problem!



ADDED: Another problem on the 3.8L (series II) engine is the plastic elbows that carry coolant to the heater hoses (one at the water pump and one at the intake) crack and will start to develope a coolant leak!

Dorman products: http://www.dormanproducts.com/p-32743-61...

http://www.autozone.com/autozone/parts/D...

same thing happened to me, i hate impalas now because of the cooling systems. i spent a lot of money on it, only to find out the head gaskets where cracked. get out from under it if you still can, maybe get you a Hyundai or a Toyota, they are very reliable if you ask me.

So once the repair is done, is there any other measures I should do to ensure that my vehicle remains running?

a plastic intake manifold, is so crappy and ridiculous.

metal is much better.

I was told that my intake manifold was cracked therefore coolant was leaking into my cylinder. The car would run out of coolant fairly quickly and overheated. The car is not running currently and I was told it was due to that leak. I have a2003 chevy impala 3.8 engine. Does this sound correct?