So last night I raced a new A6 to about 60-70mph when I remembered I needed to change he my oil catch can. So after I pulled into a parking lot and waited 20 mins before I took can off and emptied it into a bottle. Then I had a little bit of trouble putting it back but after 10 mins I got it on. I don’t know if I pulled on a hose or something but I noticed right after I started my car it sounded off. Then at the stop light, my car started to idle very oddly. Fluctuating between 600-300 really low. Started to feel like my car was gonna die, then like a Christmas tree my CEL, PCS, trac light came on. Now when I come to a stop the car feels like it’s going to die. Anyone else have any issues like this or any advice? I don’t think it has anything to do with me racing. Thanks!

 

Could be a vacuum leak happening somewhere. You might have to check all of your clamps etc. MAF sensor is another thing to check as it might be sending faulty signals.

 

I see, alright I’m gonna use my OBD2 scanner in the morning and check my hoses to see if I might have loosened something. I might have yanked on something when I was trying to put the catch can back on. I was having a hard time since I didn’t have any light and it was dark. Also, I remember when I installed my password JDM intake a while back and I left a small hose that sucked up air loose, because I didn’t know I was supposed to plug it up. It kept giving me the same light and when I scanned it, it said my engine was running lean. I checked that hose though and it’s still plugged up so hopefully it’s nothing serious. I was worried my car was gonna explode or something

 

Yeah, look at the throttle body, MAF sensor, clamps and the intake pipe area for anything loose. Usually odd idle behavior points to vacuum leak mostly in that area.

 

I’ll check it out but I don’t really know what I’m looking for so maybe I’ll take a picture and post it so I don’t screw up even more than I already did lol

 

Sounds like a vacuum leak, likely have something to do with the catch can? I'm not sure if it being full can actually cause lines to pop off. Are the lines routed back to the intake tube or just vented to atmosphere?

 

I believe the RR Racing air/oil seperator lines lead to the intake manifold as shown in this picture here (from RR Racing themselves):

 

so i thought I found the problem from a cracked hose when I moved the catch can. I think it might have cracked so the air was being let out there but I taped it up a little, and now I got the lights back on. Anyone have any advice? It smells bad btw

 

Tape will not fix the vacuum leak. Tape can still allow vacuum leak. You might have to replace it and then reset the ECU.

 

Someone told me it would be a small fix until I fix the issue. After putting tape on it, the idling isn’t as bad but still noticeable. It also reeks of gas

 

is that what it is? A vacuum leak?

 

Yeah, if you have a cracked hose then yes, it would be a vacuum leak.

 

ok thanks so much. I don’t know for sure if it’s the problem but I noticed a hissing sound coming from that area and I noticed a little bit of oil where the crack in the hose is. Do those codes represent a vacuum leak? Also , is it safe to drive? I’m sorry I don’t know much

 

A substantial enough vacuum leak will cause the engine to run rich, thus the gas smell. And can throw all kinds of codes. You'll need to replace the cracked hose. I wouldn't drive it until it's fixed, if it was my car. You could foul the spark plugs from running rich.

 

Ok thanks for the information. I was on the phone with one of the F guys I know and he helped me reset the ECU but after 5 mins the lights came back and the idling issue came back. I was driving yesterday and I noticed I had to step on the brakes a little harder than usual, I don’t know if that’s got anything to do with it. I had no idea how fragile those hoses were, I didn’t move the AOS that much when I emptied the catch can. Do you know how I can get the hose? Or the part number? Thanks for all the help guys. I have been stressing, I hope my engine isn’t going to blow up or something




this is the hose I think is cracked, as you can see the installer tightened the clamp like crazy and I guess I might have moved the hose and i think it cracked right there. There’s some electrical tape around it right now. I called a shop and they want to charge me $800 to fix this