2004 volvo s60 2.4 stalling issue

[jonesg]

A smoke test should reveal vac leak if its not obvious.

[cichy1012]

You say the engine stumbles when you apply the brake pedal. If the car is sitting still and idling smoothly will applying the brake cause it to die or does it only die if you’re driving down the road and apply the brakes?

When it starts to stumble and you quickly release the brake pedal will the engine recover to a smooth idle or does it always die once it starts to stumble? Have you tried pinching shut the hose that provides vacuum to the brake booster?

the engine will surge sometimes while driving and die. also dies ocassionally when i come to a stop. when i get someplace and throw it in park it dies. all this takes place on a constant after it starts to act up.
ive replaced
all spark plugs
throttle body
map sensor
maf sensor
cat- o2 sensor and upstream like 2 years ago i believe
fuel pressure sensor
pem module
all coils replaced.
purge valve.
ive pinched the hose going to the brake booster (pinched the right side of the hose going to booster)

i have a crankshaft position sensor that arrived yesterday so ill give that a go.

[jonesg]

it would be cheaper to diagnose it.

[cichy1012]

it would be cheaper to diagnose it.

Yea but parts that were all OG prolly needed to change anyways.

[cichy1012]

New development. So I was checking the O2 sensor on the catalytic converter and I happen to bump the cat and I heard something rattling around in there. So I took off the catalytic converter and the whole inside is shifting back-and-forth so could that be causing a blockage and causing the car to stall because at this point; obviously I need to replace a catalytic converter.