check engine light issue

[lo7100]

Hi, I have a 02 X5 3.0 with 73k on it. The check engine light was on while I was driving. I had the codes scanned as below:

P0313 misfire detected with low fuel
p0300 random/multiple cylinder misfire detected
p0174 system too lean bank 2
p0171 system too lean bank 1
p1348 cylinder #5 fuel cut off

I did a search and it looks like a vaccum leak problem. I checked the intake boots and they are fine.
Now, I'm thinking about the DISA Valve. Is there any specific noise if it's broken?

Anyway, this is my symptom of the problem.

1. little shaky when idle.
2. car stalls when it moves forward/backward slowly without stepping on the gas (ex. back out from a parking spot)
3. when it starts in them morning, the engine sounds like on and off (when it's off, it sounds like it's going to stall but it'll back up)

Otherwise, it drives fine and smooth.

Do you guys have the similiar problem before? Do you think the problem will get worse if I don't fix it soon?

Thanks for your input.