Hi guys.Hope you can help me.I have a 2004 cts with the 3.6l engine.The car has 154,000 miles on it & its a auto trans.The problem is that the car/engine stalls & when driving the check engine light is flashing.I am getting misfire codes constant on cylinders 2,4,6.Also have a TPS code.No codes for anything else.Any ideasWould a vacuum leak cause a misfire on those cylinders?Would a EGR clogged passage cause this?Thanks for your responses in advance.Will post what problem was when I fix it.Maybe be awhile

 

does the car run rough all the time
on start up

 

Yes the car would run poorly & sometimes stall.I found the problem-the ground wire for ignition coils 2,4,& 6 was not tightened down on the drivers side head properly.I cleaned the mounting point on the head,ground wire,& hold-down bolt,now the car runs great.I am surpised how powerful this engine is(3.6L).This is coming from a corvette owner.I REALLY appriciate you replying to my thread & trying to help.Thanks so much!I hate it when you ask a question on a forum & you never get any responses.Take care & thanks again