Runs rough.

Asked by Seth Nov 09, 2014 at 07:16 AM about the 1991 GMC Sonoma

Question type: Maintenance & Repair

It idles fine, but when I get into third
or more, or if I'm idling in second, it
runs really rough.But when the
service engine soon light comes on, it
runs fine. what's wrong? please help

2 Answers

30,140

you will have to read that engine code. sounds like the computer is trying to compensate for something. Google "how to read OBD1 codes with a paper clip" you will get a simple procedure for reading the code.

1 people found this helpful.
45

mine wasn't that old sounds like o2 sensor or emission problem go to and auto parts that will read your codes for free parts. for your truck are fairly cheap so even if you have to replace a couple of sensors it won't cost a arm &a leg .iban

1 people found this helpful.

Your Answer:

CarGurus Experts

  • #1
    parkle
    Reputation
    1,090
  • #2
    Mike Bonnell
    Reputation
    660
  • #3
    James Mayfield
    Reputation
    410
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet S-10
2 listings
Used Ford Ranger
22 Great Deals out of 693 listings starting at $6,445
Used Chevrolet Camaro
22 Great Deals out of 471 listings starting at $11,999
Used Dodge Dakota
20 listings starting at $3,995
Used GMC Sierra 1500
128 Great Deals out of 7,841 listings starting at $5,500

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. Content will be removed if CarGurus becomes aware that it violates our policies.