sputtering and missfiring at low rpms

2003 GMC SONOMA
4.3L • 6 CYL • 2WD • AUTOMATIC
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TV8JUNKY
  • MEMBER
  • 1 POST
Ran great earlier. Then hard to start . When it does misses badly at low rpms up to 2500 rpms. Hesitates and sputters smells a little like sulfur . runs better a higher rpms but when you stop it idles good but when you hit the gas sometimes stalls but you have to feather the gas pedal to get it to go.
Feb 14, 2014 at 2:06 PM
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OBXAUTOMEDIC
  • ✓ASE Certified Mechanic
  • 3,711 POSTS
  • ASE Certified Mechanic
Hello,

The Sulfur or Bad Egg smell it a good indication of a clogged catalytic converter. If you are able you can disconnect the front side of the cat and start it up, if runs normally then have cat replaced.
Feb 15, 2014 at 3:54 PM
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