As I went to start the Blazer, I heard a pop noise from under the hood followed by a puff of smoke and a bad smell. The engine acted funny for a little bit and then it started to idle at 2000 rpm when it normally idled at 500 rpm. The service engine light came on. I tap on the gas pedal to try to get the idle to correct itself and it seemed to have a mind of its own and jumped to 3000 rpms and then slowly went back to 2000. code given is p0101

has anyone else experienced this before?

I have tried cleaning maf sensor, checking connectors/contacts, and making sure the intake is secured on right. the air filter and tb are both clean.
is there a good, hopefully easy way, to check for a possible vacuum leak?

 

Closing this thread as I have found my issue. The PCV had broke in two parts and was allowing a rather large vacuum leak. After replacing it, truck idles at it's normal range.

 

Wow. That's kinda wild. I wonder what caused it to snap like that? Glad you figured it out quickly.

 

Thanks for the update. This will be useful for others to know.