On my 99 GT LE's intake there is an aluminum section where the thermostat goes. is this a replacement intake or is this intake the stock one that came with the car?
The thermostat housing on both intakes are aluminum. But the crossover from the thermostat housing on the driver's side head to the passenger side cylinder head needs to be aluminum, not plastic like the runners on the intake.
The crossover and whole intake for that matter should look like this:
Back in October I noticed some coolant leaking at the base where the intake manifold meets the head. Took it all apart and it was the intake manifold gasket that gave out underneath the t-stat housing area. My 99GT has 110k miles on it and I knew the history of these crappy manifolds and figured I was on borrowed time, so I replaced it with the new FRPP manifold, pretty easy job, and no vacuum leaks (thank God!!!)