dislexicmofo
Veteran Member
LARGE amounts of oil leaking through intake tract; new turbo didn't fix it; help
I have an ALH golf (2003) with a little over 200k. It is moderately modified (VNT17, plumbing, SMIC, injectors, tune). There was a large oil slick developing every time I parked. It consumed (leaked, no oil in exhaust) around a half quart over the course of 500-1000 miles. Slick would be the size of medium to large dinner plate every time I parked. You could tell it was collecting in the skid plate and then draining out behind the right front wheel.
I had several small leaks I decided to handle and a little deferred maintenance. I replaced all the CCV components. I replaced all of the easy seals: vacuum pump seal, new valve cover and sealed the corners, oil supply and return line and gaskets, oil cooler gaskets, main seal was done in the last 1k miles and did not appear to be the source. While doing this I noted that the majority of the oil appeared to be coming from the turbo outlet. There was a VERY slight leak from the crank seal. I cleaned all the oil residue up so I could better confirm the source.
The brake booster vacuum line is new. Vacuum hoses look good (car has had an easy life in the south.) N75 has been replaced previously (in the last 100k).
The leak continued, through noted source, after the other small leaks were eliminated. Confirmed through turbo outlet.
I replaced the turbocharger. The sheer volume of oil led me to believe that the oil seal was letting go. Couldn't think of anything else that would dump THAT much oil into the intake tract. Upon inspection of o-ring on the aluminum adapter it was shot (didn't have major boost issues but was enough to let the oil through). Hard and very compressed. I replaced it with a new one. Cleaned the intercooler out. Cleaned out all the piping and the intake manifold.
The oil is still leaking out. In similar volumes. I haven't had time to get under it again to confirm the location of the leak. Power output after new turbo are good (great actually).
Im at a loss at this point. What can cause that much oil in the intake tract? I have ordered a new n75 and vacuum lines in hopes that it is a horrible vacuum leak drawing that much oil in due to crankcase pressure? I'm not holding my breath.
I have an ALH golf (2003) with a little over 200k. It is moderately modified (VNT17, plumbing, SMIC, injectors, tune). There was a large oil slick developing every time I parked. It consumed (leaked, no oil in exhaust) around a half quart over the course of 500-1000 miles. Slick would be the size of medium to large dinner plate every time I parked. You could tell it was collecting in the skid plate and then draining out behind the right front wheel.
I had several small leaks I decided to handle and a little deferred maintenance. I replaced all the CCV components. I replaced all of the easy seals: vacuum pump seal, new valve cover and sealed the corners, oil supply and return line and gaskets, oil cooler gaskets, main seal was done in the last 1k miles and did not appear to be the source. While doing this I noted that the majority of the oil appeared to be coming from the turbo outlet. There was a VERY slight leak from the crank seal. I cleaned all the oil residue up so I could better confirm the source.
The brake booster vacuum line is new. Vacuum hoses look good (car has had an easy life in the south.) N75 has been replaced previously (in the last 100k).
The leak continued, through noted source, after the other small leaks were eliminated. Confirmed through turbo outlet.
I replaced the turbocharger. The sheer volume of oil led me to believe that the oil seal was letting go. Couldn't think of anything else that would dump THAT much oil into the intake tract. Upon inspection of o-ring on the aluminum adapter it was shot (didn't have major boost issues but was enough to let the oil through). Hard and very compressed. I replaced it with a new one. Cleaned the intercooler out. Cleaned out all the piping and the intake manifold.
The oil is still leaking out. In similar volumes. I haven't had time to get under it again to confirm the location of the leak. Power output after new turbo are good (great actually).
Im at a loss at this point. What can cause that much oil in the intake tract? I have ordered a new n75 and vacuum lines in hopes that it is a horrible vacuum leak drawing that much oil in due to crankcase pressure? I'm not holding my breath.
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