My wife tells me that her 08 R56 S is showing a check engine light. I take it to Autozone and they are not able to see a code. I attempt viewing any codes via the OBC but it says "check ok." I can't find really anything on the search and google so I am at a loss.

Car had warranty work down a few weeks ago due to a stuttering on acceleration due to carbon build up. Wife described the car as being normal after this service up until the check engine light came on.

I don't drive the car but now that I've been in the car trying to find the code(s) I have noticed a sucking noise coming from the valve cover near where the air filter box coming from the left side of the motor. The sucking noise is there when the car is on and for about 15 seconds after the car turns off and the sucking sound fades away. Idler pulley squeaks at idle and goes away under acceleration.

Unable to determine if these issues are related to the check engine light.

Anyone have any idea why the check engine light would come on but no codes are displayed? Warranty expired 300 miles ago so this really worked out nice and dealership doesn't have an appointment until Tuesday.

 

gas cap - did you tighten it correctly?

 

Yes. That has been checked a few times now. If it was the gas cap that initially caused it, will the check engine light reset itself or does a battery disconnect need to be done?

 

Is the sound your hearing an air sucking noise ?This could be due to an air filter/air box clogged with debris,I check mine all the time and change my filter every oil change,

 

Air filter is dirty but I don't see it causing any restrictions. Took the air filter box off just to be sure.

Here is video of what it sounds like. I think it's a vacuum leak and my wife thinks it sounds like air blowing out. Noise is coming near the crank case ventilation tube on valve cover(I have reseated it several times), the valve cover, or closer to the intake plenum. I can't narrow it down any better than that.

http://youtu.be/ArajakguJ2Y

 

It is probably a vacuum leak. If it is under warranty take it to the dealer. Have you checked the O-rings on the two PCV hoses? The PCV valve is integral with the head cover, it could be stuck too.

Dave

 

Agree sounds like a vacuum leak or vapor lock.

 

https://www.northamericanmotoring.co...26-post10.html

That description nails it and would make sense if the dealership overtightened the bolts when putting the valve cover back on after cleaning the valves.

I just hope the car is OK to drive until Tuesday. Thanks everyone.