Is any vacuum leak too much?

[packlueder]

I recently did a fair amount of maintenance: water pump/thermostat, oil filter housing gasket, and accessory belt/tensioner/pulleys. Once I got the car all back together everything seemed fine. Drove it work and back, no problems. Then I tried to accelerate onto the freeway and my car goes into limp mode. Scan the code and it is a 30FF. The only vacuum line that I was close to were these ones with the red arrow.



In order to get them off the connectors I had to cut them. I then blew into them and clamped one end off and they seem to hold the pressure. If they are actually leaking it would have to be a small leak. Would that be enough of a leak to cause the car to go into limp mode or are these lines likely not the problem? The charge pipe and intercooler connections look good as far as I can tell. The car was working perfectly (minus the leaky oil gasket and water pump) before the maintenance.

[juld0zer]

Vacuum is different to pressure. Any leak can make a noticeable difference. Looks like you may have to smoke test that vacuum tree and see exactly where it is leaking from.

[02Pilot]

Yes, any vacuum leak is enough to throw the system off. Unmetered air entering the crankcase will upset the calculations of the MAF as it enters the intake post-MAF via the PCV system. As noted, you need to perform a smoke test to locate the leak(s) and correct.