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GMC engine repair questions and answers

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  • lvinson
    lvinson - 1998 GMC Safari - Engine - 4/24/2015
    My car won't start. When I turn the key it does nothing. Could it be the starter.
    I've checked the battery terminals, made sure that the battery had a full charge, tried jumping it, and nothing. It makes no noises or nothing. Could it be the starter or is it something else?
     
    • CVO
      4/24/2015 CVO
      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.
  • John dawson
    John dawson - 2003 GMC Savana 3500 - Engine - 4/22/2015
    Where is the oil pump located on this vehicle?
    No oil pressure. Manual gauges installed and no pressure. Dash gauge no pressure. Oil warning lights on dash on. Vehicle in driveway.
     
  • Troy
    Troy - 2010 GMC Sierra 1500 - Engine - 4/22/2015
    I think my alternator went out!
    I was driving and out of nowhere my battery light came on and the display said to service vehicle charging system. I was able to get home but once I did I noticed my volts to my battery were dropping rapidly. I think it is the alternator due to it not staying ...
     
    • jdl
      4/22/2015 jdl
      I'd use a digital multimeter to verify. Everything off, place meter leads across battery posts, the generic spec for a full charge is around 12.6 volts. Start the vehicle, take second reading across battery posts, Second reading should be higher than the first if system is charging. You can also test at the alternator bat terminal.

      Could be issue with alternator wiring--alternator--battery. Some of the national brand auto stores will check battery and charging system. Battery cables ok?

      I haven't looked to see if any charging system trouble codes for this vehicle?
      jdl
      4/22/2015 jdl
      Just to add, my info was for non-hybrid.
  • Marcus
    Marcus - 1990 GMC C1500 - Engine - 4/15/2015
    Truck runs fine in park dies in gear
    Changed tps sensor and electrical Solinoid. Truck wount throw a code. Truck remains on as long as a little pressure is kept on the gas but if I let off the gas and come to a complete stop it dies and it always starts right back up.
     
    • GT500Knights
      4/15/2015 GT500Knights
      Sounds like it might be an issue with the torque converter clutch. Some vehicles have issues with the TCC getting stuck and staying locked into the engage position. A torque converter is supposed to fuckin as a fluid coupler. In park and drive while at a stop it should allow you to idle forward without stalling....this is a built in function of the torque converter. The clutch is built in to allow better gas savings and torque transfer at highway speeds...it typically will engage at above 40 mpg cruise. If this clutch is stuck engaged it will cause the car to die. Much like in a manual transmission if you let off the clutch at idle with no throttle the car will die.
  • jbuss31B
    jbuss31B - 2011 GMC Terrain - Engine - 4/14/2015
    Why wont my terrain turn over or start
    i turn the key on and everything turns on in the car and works fine but when i try to start it it does nothing. not even a click from the starter. the car only has 95k miles and is very well taken care of and has never had any problems except for a head and tail ...
     
    0 answer
  • Melissa
    Melissa - 1999 GMC Yukon - Engine - 4/12/2015
    Why won't my Yukon start?
    The problem began with the alternator. We bought a new one after having it tested and it was bad. We also bought a new battery because it was also badly drained due to the alternator draining it. We replaced both parts and now my Yukon will not start... When I put ...
     
    0 answer
  • Melissa
    Melissa - 1999 GMC Yukon - Engine - 4/12/2015
    Why won't my Yukon start?
    The problem began with the alternator. We bought a new one after having it tested and it was bad. We also bought a new battery because it was also badly drained due to the alternator draining it. We replaced both parts and now my Yukon will not start... When I put ...
     
    0 answer
  • mike1976
    mike1976 - 1999 GMC K3500 - Engine - 4/12/2015
    Truck sometimes has a very hard time starting.
    Truck has hard time starting sometimes. Truck will finally start after 20 minutes or more holding gas pedal to floor, compressing and decompressing. Fuel pump was replaced last year. It has this problem sometimes, when it doesn't do this it starts right up.
     
    • stan18
      4/12/2015 stan18
      Try turning the key on and off for 3 seconds a few times before attempting to start. The pressure may not be holding at the fuel pump causing there to be no fuel available for starting especially after sitting for some time. There is no need to press the pedal or hold it down. The fuel pump will add fuel each time you turn the switch on and off, without trying to start the engine. About three or four turns of the switch first, then try to start the engine. I have one that used to take three turns on and off and now takes four after sitting overnight. Hope this helps.
  • aklett429
    aklett429 - 1998 GMC K1500 - Engine - 4/12/2015
    What is wrong with my truck? Somethings isnt right about it.
    -Not shifting right, staying at 1000 RPM and delayed acceleration then quickly goes to 3500 RPM and sounds louder and not normal -Backfiring -when at complete stop, the whole truck shakes - smells like something burning Aftermarket Parts: New Flowmaster Custom ...
     
    • stan18
      4/12/2015 stan18
      Check the throttle position sensor(TPS). This will cause most of those symptoms if it's bad. It doesn't know how much fuel to deliver at any given time resulting in flooding, rough idle, backfiring and delayed response to the pedal or throttle position.
  • mahgurl
    mahgurl - 2005 GMC Yukon - Engine - 4/11/2015
    My check engine light was on, friend told me she used B12, two days later.CE light went off, so I used it in both of my
    vehicles, now both blows white smoke from the exhaust system and the Yukon is not registering gas I put into it. Also caught a guy under my Yukon, not sure what he did, after catching him...Yukon is not registering any gas put in, a strong gas smell is noticed ...
     
    • Jimm
      4/5/2015 Jimm
      The check engine light is located on the dash and stays on if the computerized engine control system detects an engine performance or emissions problem.

      First step - have the stored fault codes or check engine light scanned - for free - at any local auto parts store; Advance Auto, Auto Zone, NAPA. Then, post a reply as 'add answer' with the specific code for more assistance. There may be a fault code stored in the OBD memory which may not be displayed as a check engine light.

      Do not skip this important first step - there are literally hundreds of possible fault codes. Avoid wasting/ throwing money at the problem.
      Jimm
      4/10/2015 mahgurl
      Hi Jimm, thanks for replying to my question. The trouble code from OReilly's is p0332 and the code definition is knock sensor circuit low frequency (bank 2).
    • Jimm
      4/11/2015 Jimm
      Replace both knock sensors. Pay close attention to the condition of connectors and pins.

      The parts are readily available from these many on-line sources, www.partsgeek.com, www.rockauto.com, www.discountautoparts.com, www.autopartswarehouse.com, www.jcwhitney.com - to list only a few possibilities.
      In fact, they (RockAuto) list the knock (detonation) sensor from around $25.00 each for your vehicle.
  • stan18
    stan18 - 1985 GMC S15 - Engine - 4/11/2015
    How does the radiator fan clutch affect the temp. of the engine if it's going bad?
    Engine has new water pump and thermostat and radiator flush but is getting hot at hwy. speeds. At idle and low throttle position there is no overheating. Is this the fan clutch?
     
    0 answer
  • stan18
    stan18 - 1985 GMC S15 - Engine - 4/9/2015
    Why is engine now overheating after new water pump and thermostat install and only at high rpm's, not at idle?
    the water pump was bad(dripping water at hole) so i installed new pump and replaced thermostat and radiator cap just for good maintenance.I also flushed the system because vehicle had set for some time and needed it. Now when engine gets warm and thermostat opens, ...
     
    0 answer
  • stan18
    stan18 - 1985 GMC S15 - Engine - 4/9/2015
    Why is engine now overheating after new water pump and thermostat install and only at high rpm's, not at idle?
    the water pump was bad(dripping water at hole) so i installed new pump and replaced thermostat and radiator cap just for good maintenance.I also flushed the system because vehicle had set for some time and needed it. Now when engine gets warm and thermostat opens, ...
     
    0 answer
  • Tom
    Tom - 2004 GMC Sierra 2500 HD - Engine - 4/9/2015
    While driving truck goes into reduced engine power turn it off for a few seconds and restart it and it runs good.
    Replaced throttle position module
     
    • Teddy B
      4/9/2015 Teddy B
      Retrieve all vehicle module codes & google the possible causes
      for reduced power on your vehicle model engine etc

      May find something on the internet you can do

      The quickest way to resolve would be to have a
      professional with the proper test equip & experience
      find the problem,even then you may be able to talk it
      home & resolve
  • Rodric30
    Rodric30 - 2004 GMC T7500 - Engine - 4/6/2015
    Hi my name is Rodric Friendly and my truck two check engine lights come on when I drive over 65
    I changed 3 filters so I'm not sure if it's a fourth one, the oil in the primary fuel filter the air filter and you please help.
     
    • Jimm
      4/6/2015 Jimm
      The check engine light is located on the dash and stays on if the computerized engine control system detects an engine performance or emissions problem.

      First step - have the stored fault codes or check engine light scanned - for free - at any local auto parts store; Advance Auto, Auto Zone, NAPA. Then, post a reply as 'add answer' with the specific code for more assistance. There may be a fault code stored in the OBD memory which may not be displayed as a check engine light.

      Do not skip this important first step - there are literally hundreds of possible fault codes. Avoid wasting/ throwing money at the problem.