Help Pinpoint 30FF code

[30]

Seem to only get the 30FF CEL come on at a specific time. Usually happens when cruising in 4th gear at around 50% throttle it'll come on and strangely doesn't happen very often. Doesn't happen when cruising in lower gears, under WOT or full boost, always seems to only come on during partial throttle and ≥4th gear at highway speeds. The car does not go into limp mode, boosts fine imo, and runs great. The CEL always disappears after restarting the car. Car is an 08 manual and completely stock with no tune with 80k miles.

Already replaced with all new vacuum lines and both boost solenoids with no luck.

Just wanted to see if anyone here can point out something more specific before I go invest in a smoke machine and/or compressor for a pressure test, and start pulling everything apart. Thanks!

[Serhio]

Originally Posted by 30

Seem to only get the 30FF CEL come on at a specific time. Usually happens when cruising in 4th gear at around 50% throttle it'll come on and strangely doesn't happen very often. Doesn't happen when cruising in lower gears, under WOT or full boost, always seems to only come on during partial throttle and ≥4th gear at highway speeds. The car does not go into limp mode, boosts fine imo, and runs great. The CEL always disappears after restarting the car. Car is an 08 manual and completely stock with no tune with 80k miles.

Already replaced with all new vacuum lines and both boost solenoids with no luck.

Just wanted to see if anyone here can point out something more specific before I go invest in a smoke machine and/or compressor for a pressure test, and start pulling everything apart. Thanks!

[30]

For future reference if anyone has similar symptoms hopefully this will be the answer for someone else that's getting frustrating random 30FF codes that I described above.

After removing the stock air box to run the compression boost leak test, I found the hose that ran from the intake manifold that connects to the top of each diverter's nipple through a Y connector came unplugged at the intake manifold.

Also pulled off the two short hoses that connected to the DV's to inspect the condition and one of them looked frayed and split, so I just replaced all the hosing including the longer one that plugged into the intake manifold.

After plugging the hose back into the intake manifold all was well. No more random 30FF codes so far for the past week or two.

[30]

Thanks Serhio, but never experienced any wastegate issues or rattles nor was it part of my symptoms.

Although I didn't rule it out completely, since I redid all the vacuum hoses, replaced both boost solenoids, took off and tested the stock DV's, performed the boost compression leak test, all done without any issues, but if plugging in the hose that popped off did not solve the problem then I don't know what else it could be but to assume it could be the wastegate or turbo, even though both performed fine.

[Serhio]

Congratulations