Boost leak Test, Air coming out of the dipstick tube

[krawa]

is it bad to have air coming out of the dipstick when i do my boost leak test?
its not alot but it is coming out, I also can hear some liquid (oil?) bubbling when applying pressure

I've got P0299 and I think my car is in limp mode.

[cdn20valve]

is it bad to have air coming out of the dipstick when i do my boost leak test?
its not alot but it is coming out, I also can hear some liquid (oil?) bubbling when applying pressure

I've got P0299 and I think my car is in limp mode.

You need to pinch the crankcase breather hose at the TIP.

[krawa]

You need to pinch the crankcase breather hose at the TIP.

I disconnected hose that going to "pancake valve" and plug the hole in TIP before test

[walky_talky20]

This happens even with the oil cap off? You should *always* remove the oil cap when doing a pressure test as insurance against pressurizing the crankcase.

Anyway, oil bubbling and such is normal when you are applying the pressure through the turbo. The boost pressure leaks through the CHRA into the oil lines and makes that noise. It seems to happen more on turbos with lots of miles. Newer ones seem to hold the pressure better. If it leaks so much that the test isn't working, you can do the test at the lower intercooler connection. Do the pressure test post-turbo.

[krawa]

walky_talky20 Thanks,
some great points here, I did my test with the oil cap on, oops
I was suspecting turbo as the reason for underboost code, but I don't have any smoke from exhaust.

EDIT:
135K miles, turbo seems to be original.

[bagged00]

have you driven thae car yet. i wanna say if you boost leak test with the oil cap on it will cause smoke out the exhaust the next start up.

[walky_talky20]

I should add that just because it leaks pressure that way during a test doesn't necessarily say anything bad about the turbo. The way the pressure test is done (by pressurizing the turbo inlet) is not the way it works in operation. It can bleed off pressure into the oil lines but still work just fine.

[krawa]

have you driven thae car yet. i wanna say if you boost leak test with the oil cap on it will cause smoke out the exhaust the next start up.

drove the car right after with no smoke or any other issues

I should add that just because it leaks pressure that way during a test doesn't necessarily say anything bad about the turbo. The way the pressure test is done (by pressurizing the turbo inlet) is not the way it works in operation. It can bleed off pressure into the oil lines but still work just fine.

the turbo has shaft play and make dentist drill noise, so it's not in the best shape anyways.