What causes intake manifold to crack?

Intake manifolds fail because of the high levels of constantly-changing heat and pressure they are subjected to on a daily basis. The strain they are put under inevitably leads to cracks developing – it is up to the driver to diagnose the problem and deal with it at the earliest opportunity.

Why are my intake manifolds cracking and leaking?

How to replace an intake manifold in a car?

10) Remove the lower intake manifold. Remove the four middle bolts first and then the four outer. Put them in a cardboard box, punching holes and marking their locations. I had to use a crowbar on an exposed corner (very carefully) to get it out. 11) Remove the pushrods and similarly put them in a box.

How does a plastic intake manifold work in a crankcase?

A metal tube routed up through the lower metal intake manifold from the Exhaust Gas Recirculation Valve burns holes in the plastic manifold it extends into, allowing coolant to be mixed into the crankcase engine oil and combustion chambers.

Where is the intake manifold on a GM 3.8L car?

There is a plastic cover over the entire engine, which says 3.8L on it. It can be removed by unscrewing the oil filler cap and tube (counterclockwise). This allows the engine cover to be slightly tilted and freed from the rear fixture. Then the plastic intake manifold will be visible.

What causes the gasket on the intake manifold to crack?

Coolant is also distributed to the cylinders in this way. The intake manifold gasket is made of rubber or plastic and attaches the intake manifold to the engine. Due to strain from heat and the resulting contraction and expansion the gasket can get cracked.

When did GM stop using plastic intake manifold?

This plastic manifold was used on most 3.8L GM engines from 1995 thru 2005. The fix, involving replacement of the upper plastic (composite) intake manifold, gaskets, and peripherals is costly; but much less expensive than replacing the engine, which will have to be done if this repair is not completed.