Originally Posted by Katyanna

Abaya, as a former Jetta owner I can tell you that they are very sensitive to vacuum leaks. This little crack could very easily be the culprit. After doing a major overhaul on my Jetta it was running very horribly. A look at the top of the engine revealed an rather large crack right about where you mentioned. I looked at my husband(at the time) and pointed it out. Oh that is nothing.

Stubborn me.. I took out some sort of sealant and covered the leak, dried like a half hour later, restarted it. Bingo! I was right. Bottom line, I wouldn't discount that crack so easily. The sealant whatever it was held for quite some time until we forked out the money for the actual replacement part. I think it was some sort of silicon, pretty cheap investment diagnostic-wise. The actual part ran about $60 if I remember correctly.