Hi Scotty,

Thank you for all the advice on cars and your videos they are absolutely great . You are a car wizard. I have a 2001 Byick Lasebre 3.8L,done around 160K miles. Recently my intake manifold had blown up and I had a mechanic repair the car by replacing the Intake Manifold  the oxygen sensor and the crankshaft sensor as previously the car stalled a few times while driving. It had also given the bank 1 sensor 1 codep prior to the intake blowing up.

After repairing the car it runs really smooth except while it is stopped or idling the engine misses. The mechanic checked using the reader and got a P0302 code which is the cylinder #2 has a misfire. While driving and the reader is connected it shows a flat line but while it is idling the line is not flat but goes up and so forth. 

He checked the plug its ok, so is the battery. He says the wire seems to be Ok. So he does not know what is wrong. He thinks maybe when the intake manifold blew up there might have been a small piece of the manifold that may have got embedded somewhere inside but do not know. Do you have a opinion what could we check? Thanks