backfiring 2005 Sunfire

pagecountymale · 10-14-2009, 08:52 AM

I got a backfiring problem in this 2005 Sunfire, it reaches 4000 rpms and then starts bouncing rpms and then it will backfire, it had a terrible carbon build up, I flushed the engine three times,two times using Seafoam. Ithink the carbon is cleaned out now, replaced fuel injectors, fuel filter, spark plugs,fuel pressure regulator,thottle postioning sensor,maf sensor,upper h2o sensor. I wonder if the EMC (spark controll computer located on the top of the engine beside the spark plugs)is tthe problem, or fuel pump is breaking down on pressure?

**Raylo** · 10-14-2009, 04:38 PM

Did you ckeck/clean/change the EGR valve?

10-14-2009, 08:52 AM	#1 (permalink)
pagecountymale Registered User Join Date: Apr 2009 Posts: 1 OS: Windows XP	backfiring 2005 Sunfire I got a backfiring problem in this 2005 Sunfire, it reaches 4000 rpms and then starts bouncing rpms and then it will backfire, it had a terrible carbon build up, I flushed the engine three times,two times using Seafoam. Ithink the carbon is cleaned out now, replaced fuel injectors, fuel filter, spark plugs,fuel pressure regulator,thottle postioning sensor,maf sensor,upper h2o sensor. I wonder if the EMC (spark controll computer located on the top of the engine beside the spark plugs)is tthe problem, or fuel pump is breaking down on pressure?

10-14-2009, 04:38 PM	#2 (permalink)
Raylo TSF Enthusiast Join Date: Feb 2006 Location: Maryland, USA Posts: 524 OS: XP Desktop, Vista HP Notebook, XP Notebook	Re: backfiring 2005 Sunfire Did you ckeck/clean/change the EGR valve?