bad turbo cause blowby?

so my jetta that got a motor put in it with new head gasket and old turbo and used block started fine, took it for a test drive today. was in limp mode.

brought it back. realized I had a vacuum issue sorted that and took it back out for a test drive.


ran beautiful for about 4 miles and the turbo blew, limp mode, clouds of smoke etc. when I pulled off road noted that it had oil all around dip stick which was loose and smoke rolling up out of the dipstick hole as well as pouring out of the back.

towed it home and parked it , I am done for now have some actual things to do for a bit in the shop and then will play with it another day.

my question is lets assume the used turbo I put on it from the donor car which I have never seen run failed. it looked ok but I did not have a turbo for it so I gambled on the used one on the block with the spun belt.

assuming it failed which seems 100 percent likely would this in any way cause the smoke to be rolling out of the dipstick with oil splattered around it from the pressure or can I assume two things failed due to it suddenly also having increased blowby? or is this related to a failed turbo somehow?

I am just wondering if two things went wrong when the turbo failed because it was definitely not spraying oil and smoke out of the dipstick hole prior to the run or at any point idling. this only happened after a turbo on run which ended in turbo failure.

I didn't want to run it long because I had no idea if it was fixing to run away or if it was trying to ingest metal. no crazy sound overall just a weird noise and then lost power and had a cloud of smoke the size of a small a bomb when it went at about 70 mph on a test run.

this engine idled fine for a few hours, and it ran with out vacuum to the turbo and did just fine although clearly underpowered. made it a few miles with boost running great and blew.

any thoughts?

I will be compression checking it when I get time and pulling turbo for inspection but the dipstick thing was weird, sudden onset and I am just trying to understand what might have happened?

so much for this project being done soon. good thing it is a spare for a spare that I got just because. looking like it may end up a parts car yet

Yeah the engine ingested oil and you are going to have bent rods, the compression test you have planned will show that.

I had not thought about that first time a turbo has done that on me, had one fail before but it was kind enough to make a lot of noise so I could inspect it.

this one just blew

, that sounds likely a very likely explanation. I will compression test it at a later date and update this. I did order a diesel compression tester the other day as an ominous feeling told me too lol...

will check it before the block comes out and update thread

Don't forget to spin the engine with the plugs out to blow any residual oil out of the piston bowls before testing.

As for the pressurization of the crankcase, one pathway is for exhaust to enter
through the turbo housing and into the oil drain if the turbo shaft has snapped.
Let's hope that there isn't a hole where there shouldn't be one.