986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Will a vacuum leak on the AOS affect the right bank more?

Dale_K · 03-03-2011, 08:24 AM

I jacked the car up and poked around with the propane torch turned on but unlit trying to provoke a response that I could hear such as a rising rpm. No dice on the propane but I'm pretty sure I found the leak just by probing around and moving things.

I could hear a little hissing sort of at the center of the top of the engine. If I move the rear of oil fill tube gently I can hear a very distinct change in the sound (louder) and also the motor runs different at the same time. I couldn't get any similar reaction when I pushed the AOS bellows with my fingers. I'm almost positive the vacuum leak is the oil fill tube.

BTW, and not to hijack my own thread, but my hat's off to you guys who have replaced the AOS yourselves. I had the pictures from the 101 projects and it looks like a piece of cake. In real life that job looks like a nightmare. The oil fill tube looks like a tough job too but I'm still pleased to find a real issue to focus on instead of just replacing a bunch of parts on hope & prayer.

03-03-2011, 08:24 AM	#12
Dale_K Registered User Join Date: Dec 2010 Location: Hot Springs Village, Arkansas Posts: 245	I jacked the car up and poked around with the propane torch turned on but unlit trying to provoke a response that I could hear such as a rising rpm. No dice on the propane but I'm pretty sure I found the leak just by probing around and moving things. I could hear a little hissing sort of at the center of the top of the engine. If I move the rear of oil fill tube gently I can hear a very distinct change in the sound (louder) and also the motor runs different at the same time. I couldn't get any similar reaction when I pushed the AOS bellows with my fingers. I'm almost positive the vacuum leak is the oil fill tube. BTW, and not to hijack my own thread, but my hat's off to you guys who have replaced the AOS yourselves. I had the pictures from the 101 projects and it looks like a piece of cake. In real life that job looks like a nightmare. The oil fill tube looks like a tough job too but I'm still pleased to find a real issue to focus on instead of just replacing a bunch of parts on hope & prayer.