Rough idle and bubbling noise under cab

Asked by Jan 19, 2017 at 11:34 PM about the 1991 GMC Sierra 1500 C1500 SLE Extended Cab LB

Question type: Maintenance & Repair

I have a 91 GMC Sierra 1500 5.0 .  It idles
rough at low speed sometimes  stalling .
Runs  fine  at a higher speed .  There's also
a bubbling noise under the cab  like it's
coming from the muffler . But the noise
doesn't always happen .  I have changed
the idle  control valve PCV valve and  fuel
filter .

2 Answers

116,315

Maybe you have a exhaust leak. Take it to a muffler shop. The rough idle could mean you need a tuneup or that the IAC is dirty or needs replacing.

What is the idle at? Maybe try running a can of sea foam through it

Your Answer:

GMC Sierra 1500 Experts

  • #1
    dragonflyoffshore
    Reputation
    5,610
  • #2
    John Saffrahn
    Reputation
    3,940
  • #3
    Glenn Clingenpeel
    Reputation
    3,750
View All

Related Models For Sale

Used Ford F-150
2,303 Great Deals out of 198,316 listings starting at $1,277
Used GMC Yukon
303 Great Deals out of 22,479 listings starting at $2,499
Used Chevrolet Camaro
260 Great Deals out of 27,187 listings starting at $2,900
Used Ford Mustang
309 Great Deals out of 40,138 listings starting at $1,000

Used Cars For Sale

2018 GMC Sierra 1500 For Sale
53 Great Deals out of 33,849 listings starting at $20,490
2017 GMC Sierra 1500 For Sale
148 Great Deals out of 5,499 listings starting at $18,250
2016 GMC Sierra 1500 For Sale
56 Great Deals out of 2,795 listings starting at $15,995
2015 GMC Sierra 1500 For Sale
85 Great Deals out of 4,717 listings starting at $11,995
2014 GMC Sierra 1500 For Sale
74 Great Deals out of 2,816 listings starting at $9,900

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.