Jump to content

acceleration/power issue

notAmechanic
 Share

Recommended Posts

notAmechanic New Member

notAmechanic

Posted
Posted

If this has already been asked, please point in the right direction. I have a 2015 GMC Sierra, 96K miles. This is really hard to explain. When getting into the throttle on take off, the truck will bounce and jump 3 or 4 times before taking off. It is almost like running out of gas. This issue has almost got me ran over cutting across traffic.  If you get into the throttle easy this issue does not occur. Only on mid/hard acceleration.  The tack will also bounce when this occurs. Sometimes the tack will quit all together, not every time. When the tack quits then i cant replicate the issue. I have to turn truck off and back on to get tack to function again.  When this occurs it throws no codes or lights. If you have it hooked to a computer while driving it will give a crank sensor fault. I recently replaced the transmission and crank sensor. This issue happen repeatedly before trans. change.  I have also recently replaced the high pressure fuel pump.  If any one could point me in the right direction i would appreciate it.  

 

 

 

 

 

 

 

WT35002017 Enthusiast

WT35002017

Posted
Posted

I personally have not had this problem but it seems that many of these trucks suffer from bad ground connection issues. Sometimes it is a ground connection installed on a painted stud and nut, sometimes it is the wire connected to the negative battery terminal. A bad ground connection can cause the issue you are having. Search this issue on the web, you will easily find videos of where they are and how to fix these known issues. Good luck!

  • 2 weeks later...
rlcole321 Enthusiast

rlcole321

Posted
Posted

possibly bad plug wires, grounding to engine, try, when engine is hot, spaying water (spray bottle) around the spark plug boots, if bad wires you may see or hear the bad one(s) arcing to the engine causing misfire.

16LT4 Enthusiast

16LT4

Posted
Posted

Tach gets its signal from CkPS, so it still reads like an issue with that sensor.  Did you replace it with a quality sensor like Siemens, VDO, or GM Genuine?  If not, the sensor is just new and not necessarily good.  Don't forget to clean its connection and inspect its wires for a short.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • newdude
      Gas fill door

      By newdude · Posted

      Common failure.  You need to replace the fuel door housing.   The painted cover transfers over to the new housing.  To remove the old one there is 4 spots where you poke the plastic to release it.  
    • newdude
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By newdude · Posted

      No such thing as regenerative braking on a pure ICE vehicle.     Regenerative braking is the re-capture of energy from electric motors and stores it in the battery pack.  So hybrids, PHEV and EVs have regenerative braking.     What you are seeing is the charging system changing modes is all.  Its likely entering charge mode for some sort of reason is all.  All of the charging modes will be listed below.   As for L10 vs D.  L10 turns off automatic grade braking.  L10 puts you in control of grade downshifts where in D it will automatically do it based on brake pedal position and other factors.  Otherwise L10 and D drive exactly the same aside from that one aspect.    Battery Sulfation Mode The BCM will enter this mode when the interpreted Generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements.   Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met:   Windshield wipers are ON for more than 3 s. Climate Control Voltage Boost Mode Request is true, as sensed by the HVAC control module via serial data. High speed cooling fan, rear defogger, and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. The estimated battery temperature is less than 0°C (32°F). Battery State of Charge is less than 80%. Vehicle speed is greater than 145 km/h (90 mph) A current sensor malfunction exists. System voltage is determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature.   Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 A and greater than −8 A, and the battery state-of-charge is greater than or equal to 80%. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. When fuel economy mode is active, the generator is not charging, only maintaining open circuit battery voltage. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present.   Headlamp Mode The BCM will enter Headlamp Mode when ever the head lamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V.   Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 s.   Tow/Haul Mode (if applicable) Pressing the Tow/Haul Mode button located on the center stack, the vehicle system voltage is raised and the remote (non-vehicle) battery will be charged. Having the headlamps on will raise the system voltage and if the Tow/Haul button is applied it will not serve any purpose. The voltage is regulated between 13.9-14.5 V.      
    • jaszr2
      Active Grille Delete

      By jaszr2 · Posted

      Hello from Australia Just sharing that there is now a way to delete the active shutters entirely with just a plug in module. Opens up tons of room to light bars etc.
    • jake111
      Gasser Subforum Has Been Quiet - - So, Regenerative Braking and Using L10

      By jake111 · Posted

      I have an observation and a question... 1) I watch the voltage closely because I have had to dial in the cut-in/cut-out voltages of the battery separator to my camper.  The "smart" charging drives me nuts.  Anyway, I noticed that when coasting for a while, and especially if lightly using the brakes (though not necessary), the voltage goes up from mid/high-13 volts to mid/high-14 volts.  Then it drops back down after stopping or going again.  Consistently!   The only explanation I can come up with is REGENERATIVE BRAKING!  Well, maybe that's a little bit of an exaggeration, but it's certainly free extra battery charging.   2) Driving on mountain roads I will use L and vary the max gear.  Things straighten out and I end up in L10.  Sometimes I leave it there for a while.  Is there any difference between L10 and D?   
    • devonthegreat
      anyone interested in a 2002 Chevy Silverado 4x4 parts truck NYC

      By devonthegreat · Posted

      **SOLD** Please end or delete post. thank you

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...