1990 k1500

Asked by Brian Nov 07, 2017 at 08:35 PM about the 1991 Chevrolet C/K 1500 4WD

Question type: Maintenance & Repair

my 91 k1500 runs rough idles rough but when you
first start it its not as bad but after a minute or two
it cuts out every time you give it throttle and it
barely idles at all

1 Answer
145

John answered 7 years ago

sounds like fuel delivery issue or a vacuum leak. Could be clogged injectors, fuel filter of fuel lines. Could be the fuel pump is dying. On these trucks the fuel pump only works if oil pressure is present and seen by the ECU so a bad oil pressure sending unit could be the issue. Start with the Basics- Fuel/Air/Spark/Compression Fuel- is it getting adequate fuel? Measuring fuel pressure at the throttle body injectors will tell you. AIR: Is the MAF sensor telling the ecu bad info? Cleaning it with MAF cleaner may solve the problem. Also check for cracked or loose hoses and fitting between the air box and the throttle body that may be letting in unmetered air. Spark- Since it will start, you have spark. May cause this problem if weak but not likely culprit. Compression- If the truck has been burning oil for awhile you may have a worn out set of valves or rings causing massive misfire. Less likely Most likely a dirty MAF sensor or clogged fuel delivery (pump, filter or injectors)

Mark helpful

Your Answer:

Related Questions

  • 1990 k1500 1 Answer

    my 91 k1500 runs rough idles rough but when you first start it its not as bad but after a minute or two it cuts out every time you give it throttle and it barely idles at all

    1991 Chevrolet C/K 1500 4WD

    -

    Maintenance & Repair

  • 1990 gmc k1500 electrical problems 1 Answer

    I have a 1990 k1500 5.7 tbi the truck has no power in the cab no headlights and no 4 ways as well as the gages dont work ive check the main power block on the exterior fire wall and i have power in...

    1990 Chevrolet C/K 1500 Silverado 4WD

    -

    Maintenance & Repair

  • 1990 k1500 3 Answers

    how do i tell the difference between a 305 and 350 in my 1990 k1500 4x4

    1990 Chevrolet C/K 1500

    -

    General

  • 1990 Chevrolet k1500 tail light not working 1 Answer

    My 90 Chevy k1500 tail lights do not come on when turned on. I have no brake lights. The blinkers and flashers work but slowly. If the blinker or flashers are on and the brake is applied the bul...

    1990 Chevrolet C/K 1500 Stepside 4WD

    -

    Maintenance & Repair

  • 1990 k1500 1 Answer

    my truck runs ruff until i unplug the vacum line thr big 1 on the back of the throttle body it dosnt cut out but blows black smoke if i plug it in where its supposed to be it idles for a second and...

    1990 Chevrolet C/K 1500 4WD

    -

    Maintenance & Repair

Shortcuts

Search Chevrolet C/K 1500 Questions

CarGurus Experts

  • #1
    Andrew Olsen
    Reputation
    15,950
  • #2
    Rowefast
    Reputation
    9,670
  • #3
    John Saffrahn
    Reputation
    6,480
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used GMC Sierra 1500
148 Great Deals out of 7,258 listings starting at $3,950
Used Ford F-150
321 Great Deals out of 14,968 listings starting at $1,712
Used Chevrolet C/K 2500
1 listing
Used Chevrolet S-10
3 listings starting at $12,975
Used Chevrolet Corvette
29 Great Deals out of 1,060 listings starting at $15,871
Used Chevrolet Camaro
16 Great Deals out of 307 listings starting at $10,500

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.