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GMC engine repair questions and answers

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  • Wayne
    Wayne - 1998 GMC K1500 - Engine - 9/17/2014
    Have whine coming from the front engine compartment that comes with rpm until around 2500.
    Replaced PWRs st fluid and flushed system and it got a little better. Could it be anything other than the pump? Has 190k and don't want replace it needlessly.
     
    • alex
      9/17/2014 alex
      take the belt off and rev it up if the noise is still there you know it is in the accessories spin everything by hand while pushing or pulling on then everything should be tight and smooth any roughness will turn into belt noise look at all of the pullies with teeth they shouldn't have a sharp edge on them if they do the pully is wore out if everything looks and spins good replace the tensioner. you should have to twist it pretty hard to get the belt off.
  • marcia
    marcia - 1994 GMC C1500 Suburban - Engine - 9/13/2014
    It won't start has new starter and battery there is power but it doesn't turn over whats wrong?
    could it be a fusible link?
     
    • CVO
      9/13/2014 CVO
      First, check the battery and starter cables for their tightness or free of corrosion and physical damaged.

      See this Starting system simplified diagram. Have a help from an assistant to crank the engine, use a 12 volt light tester or a digital voltmeter, apply it to the starter control circuit.
      If there is light or 12 volts and the starter isn't cranking, then the starter is the culprit. Have the starter to bench test for free at the local auto parts stores.
      If there isn't no light or no volts, then the ignition switch is the culprit.
      Check the starter relay and position the Automatic transmission shifter in neutral.

      http://www.samarins.com/glossary/starter.html
  • Uflores
    Uflores - 1994 GMC C1500 Suburban - Engine - 9/9/2014
    Why does my car turn off at a stop sign?
    When I turn on the car the car takes awhile to start than normal. When you are at a complete stop the RPM starts going up and down between 0 and 1, and then turns off. It also turns off when your about to reverse. I work at a car dealership and no mechanic in the ...
     
    0 answer
  • Barb.desrosiers
    Barb.desrosiers - 2008 GMC Envoy - Engine - 9/7/2014
    What is wrong with my car? see additional details
    Initially I was having trouble starting the car. I would get a click click whine noise, then sometimes I would turn key and nothing happened, I would turn key 3 or 4 times with nothing happening, then all of a sudden it would start. Then I was sitting at a stop ...
     
  • Barb.desrosiers
    Barb.desrosiers - 2008 GMC Envoy - Engine - 9/7/2014
    What is wrong with my car? see additional details
    Initially I was having trouble starting the car. I would get a click click whine noise, then sometimes I would turn key and nothing happened, I would turn key 3 or 4 times with nothing happening, then all of a sudden it would start. Then I was sitting at a stop ...
     
    • CVO
      9/7/2014 CVO
      This vehicle has a similar problem to this post.

      http://www.automd.com/.../


      Try this tip.

      First, check the battery and starter cables for their tightness or free of corrosion and physical damaged.

      See this Starting system simplified diagram. Have a help from an assistant to crank the engine, use a 12 volt light tester or a digital voltmeter, apply it to the starter control circuit.
      If there is light or 12 volts and the starter isn't cranking, then the starter is the culprit. Have the starter to bench test for free at the local auto parts stores.
      If there isn't no light or no volts, then the ignition switch is the culprit.
      Check the starter relay and position the Automatic transmission shifter in neutral.

      http://www.samarins.com/glossary/starter.html

      Note: a 3/4 charge battery is 12.50 volts
      A discharge battery is 11.75 volts.
      A battery under a cranking load and it is reading less than 7 volts,it will be a recycled battery.
  • msyoung
    msyoung - 1997 GMC K1500 - Engine - 9/4/2014
    Will not start turns over just doesn't stay onthis happened after running out of gas & putting out in neutral to star
    Recently changed fuel pump and filter
     
    • jdl
      9/4/2014 jdl
      Did you check fuel pressure? If you have the spider fuel system, that system is known for problems. How long since over-all tune-up? Any applicable trouble codes? To check codes yourself, at the least you need an obd2 code reader.

      Can you tell if your losing spark--fuel pressure or something else?
      jdl
      9/4/2014 msyoung
      Did change spark plugs and haven't yet check the fuel pressure no check engine light so no code..
      Someone had said it might be starter idk
      jdl
      9/4/2014 jdl
      I always check for codes, I've had inactive codes point me in the right direction. I don't think I understood your last sentence? If it cranks ok, the starter isn't the problem.
      jdl
      9/4/2014 msyoung
      Humm im going to have to try the code scanner
      Wish I could post a video of what it is doing
      jdl
      9/5/2014 jdl
      A start and stall could be caused by almost anything. Maybe your losing rpm signal--fuel system is running too rich or too lean for some reason. Anti-theft issue where applicable. Many possibilities.
  • ken lehtonen
    ken lehtonen - 2005 GMC C5500 Topkick - Engine - 8/29/2014
    Diesel engine wont start . when it starts it runs good
    seems like an electric problem , no power to fuel pump when trying to start but when it starts it works fine. replaced fuel filter and pumped up fine started and ran shut off and wont start
     
    0 answer
  • coreybaker86
    coreybaker86 - 1995 GMC K1500 - Engine - 8/28/2014
    No power to the OBD2 connection.
    Recently bought the truck and it runs good but cruising around 55 the engine rev's up suddenly by maybe 500-700 rpms then goes back to normal. I cant accelerate during this either. I plugged in a scan tool and it wouldnt turn on. I checked the scan tool on my other ...
     
    • jdl
      8/28/2014 jdl
      Some gm makes and models, 95 is a crossover year, It could be a hybrid connector, I can't you with that type connector. I'll check your wiring diagram.

      If you fully obd2 compliant, pin 16 should be hot. That voltage usually comes from cigar fuse, I'll have to double check.
      jdl
      8/28/2014 jdl
      If your system is obd 1.5, then you will need a scanner for obd 1.5.
  • glen
    glen - 2001 GMC Sonoma - Engine - 8/26/2014
    No start intermittent
    intermittent crank but no start fixes itself after days or weeks of trying to start it
     
    • jdl
      8/26/2014 jdl
      When the problem is ongoing, if it cranks good but won't start, have a helper crank it while you visually check for spark at the spark plugs. If you have spark everywhere, check fuel pressure. With intermittent issues, you need to test when problem is ongoing.

      Check for intermittent rpm signal? No rpm signal, no start. Can be intermittent.

  • glen
    glen - 2001 GMC Sonoma - Engine - 8/26/2014
    Intermittent no start
    mileage 125000 cranks but no start can happen anytime works fine most of the time but will leave you stranded let it sit for days or weeks and eventually starts and acts normal until next episode of no start
     
    0 answer
  • rlhanson58
    rlhanson58 - 2008 GMC Acadia - Engine - 8/25/2014
    Where is my oil pressure switch located on my engine.
    Having a problem with low oil pressure. I check oil it's fine. This only happen on a long trip. light come on dash board.
     
    0 answer
  • ql_lp
    ql_lp - 1993 GMC C1500 - Engine - 8/21/2014
    Truck starts when it wants to.
    Every once in awhile my truck won't start as if the starter was disconnected. But by leaving it for 30 to 45 mins it starts as if nothing happened. There is another way to start it quickly by boosting it off. Looking at the schematics it's pretty simple system. I ...
     
    • jdl
      8/21/2014 jdl
      I'd have to check starter electrical circuits when problem is ongoing, voltage and ground. Any testing at the starter, make sure tranny is in park or neutral and a functional parking brake is set.

      Make sure your battery has a full charge. The starter solenoid s terminal gets voltage from the ignition switch crank position then through the neutral switch, usually. I haven't looked at your wiring, yet. Use a digital multimeter and do some circuit testing, have a helper turn key to crank.
  • ql_lp
    ql_lp - 2007 GMC Sierra 1500 - Engine - 8/20/2014
    Sometimes the truck won't start as if no starter.
    Every once in awhile my truck won't start as if the starter was disconnected. But by leaving it for 30 to 45 mins it starts as if nothing happened. There is another way to start it quickly by boosting it off. Looking at the schematics it's pretty simple system. I ...
     
    • Chevy doctor
      8/20/2014 Chevy doctor
      Sounds like a ignition switch problem. We have had issues with the under hood fuse block failing internally.
  • Wayne
    Wayne - 1998 GMC K1500 - Engine - 8/19/2014
    Have whine coming from the front engine compartment that comes with rpm until around 2500.
    Replaced PWRs st fluid and flushed system and it got a little better. Could it be anything other than the pump? Has 190k and don't want replace it needlessly.
     
    0 answer
  • Jacob
    Jacob - 1994 GMC K1500 - Engine - 8/18/2014
    Why is my truck idling and driving rough
    I have a question so I have a 94 gmc serria with a tbi 350. When it starts up the idle is really low. And drives really sluggish. It sounds like it has an upgraded cam in it but my truck does not. Don't know whats wrong with it any ideas. I just had a new intake ...
     
    0 answer