I have a 97 Jetta GT and when I was changing the air filter I noticed that there was oil in the intake air duct. What would be causing this? I just bought the car used so I don't know the history of it. Thanks for any help.
A slight amount is normal. As for causes: 1-oil overfull, 2-breather system has leaks, 3-blowby from rings. Also depending there was an tech bulletin
24-99-04 for 96 to 98 2.0l engines which address this issue. BTW it's not free repair from VW so don't get your hopes up!
PCV flap not working properly. IOW staying open.
Could be the valve cover ventilator blowing oil into the intake. I don't know about your car, but the ventilator hose from my Fox valve cover runs to the intake boot, just before the throttle body... and when I recently took my boot off I saw the oil. I cleaned it, but I asked around and was told it was no big deal.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.