I have a 2008 Suburban LTZ 4WD that has 59k miles on it. Recently I have noticed that the RPMs will fluctuate occassionally when I am trying to hold a steady speed around 30-40 MPH. The RPMs jump between 750-1200 RPM. It only does it when I am barely giving it gas to just maintain a slow speed and it will do it as long as I let it go until I give it more gas then it goes away. It runs great other than this issue and I have not done anything lately as far as service or changing out any parts. I am wondering if it is a MAF, throttle body or throttle position sensor issue. Does anyone have any insight into this? I know if I take it to the local dealer they will not be able to duplicate my concern or will say it is operating as normal. Thanks in advance for your input.

StormH2Oguy

 

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I am sorry to hear of your RPM issue on your Suburban. Is this an occasional issue or recurring? I have not been able to find any known RPM issues for Suburbans in my resources. Have you already taken the vehicle in for an inspection and they weren't able to duplicate the problem? Could you please PM me your VIN number so I can research this further?

I look forward to your response.

Louis
GM Customer Service