How to check engine vacuum hoses<br>Check each hose for bulges and swelling. If a hose feels soft or spongy when you touch it, this can indicate damage caused by your car's oil. [substeps] A swollen hose that is cracked and hard is often caused by heat damage.
Heat is the primary cause of damaged hoses
( z1 cause :ARG0 ( z2 heat ) :ARG1 ( z3 hose :ARG1-of ( z4 damage ) ) :mod ( z5 primary ) )