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Rough Idle

Ragsy1083

By Ragsy1083
in Ask A GM Technician

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Ragsy1083 Enthusiast

Ragsy1083

Posted
Posted

So recently I've noticed that my 2011 Sierra 1500 is idling rough whenever I have to come to a stop, with a noticible shudder at times throughout the truck. I took it to my local dealer and they determined that the throttle position sensor was bad and replaced it. It was okay for a day, but the shudder came back today on the way home from work. I've tried different gas stations thinking it might be the gas (dealer's other idea)with no change. Any ideas?

 

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nht mike Enthusiast

nht mike

Posted
Posted

I just got a letter from GM on that same problem today. it doesn't have a service number with it, but it does say they will cover the problem for 10 years or 120,000 miles. So you are not alone!

 

Mike

scooby5121 Enthusiast

scooby5121

Posted
Posted

So I guess the problem is top secret !!! and you have to bring it in on warranty so they can fix it ( if I am reading your post correctly)

 

Scooby. Pls Post the Fix after you get it back under warranty from the Dealership.

demech23 Enthusiast

demech23

Posted
Posted

As long as there are engine trouble codes present the dealership is allowed by warranty to remove your throttle body, open it up, replace the black over and install new contacts, and then reinstall it on the vehicle. If no trouble codes present usually service advisors try to see a throttle body and/or fuel injection cleaning service and blame it on non-top teir gas and/or ethanol.

Ragsy1083 Enthusiast

Ragsy1083

Posted
  • Author
Posted
I just got a letter from GM on that same problem today. it doesn't have a service number with it, but it does say they will cover the problem for 10 years or 120,000 miles. So you are not alone!

 

Mike

 

I got that same letter and took it with me to the dealership when I went the first time, and they said that wasn't the issue because there were other symptoms for that fault that I wasn't having (check engine light; stabilitrak off; severely sluggish response)

 

I'm taking it back in on Monday and dropping it off...hopefully this time they can figure out what's going on

  • 2 weeks later...
Ragsy1083 Enthusiast

Ragsy1083

Posted
  • Author
Posted

So even though they said they checked the spark plugs, the tech looked farther back into the computer history and found that one of the plugs had a misfire. Sure enough the plug was cracked. Replaced the plug and sounds as good as ever

 

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Black2011 Enthusiast

Black2011

Posted
Posted

Its nice to hear a dealer taking it upon themselves to find the root cause of a problem. Now they just need to make sure it happens on the first service visit.

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