hello, about a month ago, my jetta's check engine light would seem to randomly turn on and off every few days. Eventually, I realized it was lighting up everytime I started the car with the A/C on. Any ideas?
Also, this got me curious so I was listening under the hood and I heard a hissing on the right side of the engine(just to the left of the MAF).
Any help would be appreciated. Feel free to ask questions. Thanks all.
Matt

 

Is your AC cold? I dunno bout no hissing sound, but I could only imagine.

 

I had a problem similar to that but mine was the emergency break light sensor had went bad (which come to find out they had a factor recall on the sensor)
anyways it was connecting to my circulation button. so everytime that I have to defog my windows i had to take turn off the circulation button and have the emergency brake light come one.

You might need to contact your local VW dealer to see if they might know of any problems that have to do with that.

 

the hissing sound might be a cracked hose. i had a similar problem once & when i looked, i saw one of the hoses near the throttle body was sliced & was sucking outside air. that was what was causing the sound. went to advance auto n got a new piece for like $2.