Bled the system, did a block test, and ran a compression test. Still bubbling, no CO2 or loss in compression.

I feel the hose for the compression test could've been screwed in tighter but I the hose spun so I wasn't able to get it fully sealed. Compression for all 4 chambers ran approx 105-110. I'm sure I would've had higher values if it was sealed into the spark plug better. Numbers were consistent though.

 

I've had the same compression hose problem before. Shitty design I guess.

As long as the pressure readings are consistent on all 4 cylinders, then you're good.

Honestly, if it's not causing you a problem, I'd forget about it. If the tank over-pressurizes, there's a safeguard in the lower back corner of the tank that will bleed out once X amount of pressure is built.

G/L

 

I took it to Audi yesterday to get a quote on a new expansion tank cap (27.99 holy ****). Decided to talk to one of the service experts and he asked his mechanic about it. I told him that it burbles when the AC is on because that's what I noticed it yesterday when I did the compression and block tests. The mechanic said since it's only when I turn the AC on, I have an air pocket in the heater core or it's clogged. I guess it makes sense since I don't have heat either. So I'm gonna clear it hopefully soon. Haven't had heat since I bought the car so I think it's time. Thanks for the help man! Appreciate it.

 

My pleasure.

Try turning it on and letting it idle, with the heater on high for about ten minutes (with the cap off). Then do the same thing with the A/C on high. See if that pushes all of the air out.

G/L