Intake manifold boot
 

Lioking at a car that's having it's intake manifold boot replaced because it cracked. Then the replacement cracked when the mechanic test drove the car. Is there anything more serious lurking or just a bad part or install?

Are you talking about the large rubber coupler? If so, that would be mechanic fault. Those things when new are very flexible and durable.

Yes, exactly. Didn't seem like something that should cause problems. Not sure why there isn't a metal band through the middle of it unless it needs to flex a lot.

What year is the car and what are you calling the intake manifold boot. Most intake rubber never cracks, it usually swells and gets soft because of oil in the intake tract over the years.

It's a 1980 euro S. I'm talking about the 4" sleeve between the upper and lower intake. It's held in place by two clamps.

I replaced mine with a new one just about a month ago. Old one was hard and brittle. The new one was soft as a radiator hose when i installed it. I do not see how it could crack in the slightest unless it was damaged going on. They are not the easiest things to install while making sure you have it sealed properly.

He is talking about the 4" diameter hose between the upper and lower plenum.

I've seen both, either balloned up by oil or hard and brittle. Either way, a new one will not break unless the coupler was defective to start with or your mechanic is defective.

If it's a Euro you can't order a normal one (US too small). I believe you need to use the one from a 32v 5 liter.

Sounds like the problem maybe, mechanic tried to stretch a US part on the larger Euro throttle body and intake.