Search results

  1. T

    I want to delete or bypass the EVAP system in this 2012 Yukon Denali

    Sick of this EVAP system and want it gone or bypassed. Anyone already done it? I have been through the entire system and replaced all EVAP parts a few months ago and now I'm back to the pump shutting off again. I'm done with this and want it gone.
  2. T

    2012 Yukon Denali 6.2. Poor gas mileage, no codes thrown and no check engine light

    Well that didn't work. There must be a reset or relearn for the MPG display because now it shows 6.4mpg.
  3. T

    2012 Yukon Denali 6.2. Poor gas mileage, no codes thrown and no check engine light

    This is a new symptom after replacing the new parts I mentioned. I don't understand why the computer would display the AVG mpg declining while the truck is sitting still? You are right about the weather being hotter now than before. I assume if the O2 sensors are bad it would throw a code?
  4. T

    2012 Yukon Denali 6.2. Poor gas mileage, no codes thrown and no check engine light

    While sitting in the truck at idle I can watch the computer display "Average fuel mileage" it starts dropping while just sitting there. 1/4 tank of gas in it. The computer started at 8.2mpg which is low and in about 15 minutes the computer read 6.9 mpg. My wife is complaining that this truck is...
  5. T

    2012 Yukon Denali 6.2L 6spd transmission hard shift from 1-2. Shakes truck

    This is the stock transmission and nothing has ever been towed with this vehicle. Less than 200000 miles on it and never been off road as its a kid hauling grocery getter. Recently while on a trip to North GA I noticed while taking off from a dead stop the car shifted hard from 1st to second...
  6. T

    2012 Denali with 6.2 engine shutting off while driving. Random

    I have a rather expensive OBD reader that can view everything you mentioned. I'll report back what I find and thanks
  7. T

    2012 Denali with 6.2 engine shutting off while driving. Random

    Did this and thanks
  8. T

    2012 Denali with 6.2 engine shutting off while driving. Random

    No issues with electrical at anytime. I'm leaning towards a fuel pump assembly getting ready to fail but no hard starts or stumbling of engine. It just shutoff like someone flipped a switch.
  9. T

    2012 Denali with 6.2 engine shutting off while driving. Random

    Two weeks ago my wife was driving this Yukon down the road at 45mph and the engine shutoff. She coasted to the side of the road. She shifted it to park and it immediately started back up and no problems the rest of the day. Earlier this week she got in the car in the morning and when she stopped...
  10. T

    2008 Yukon gas tank issue.

    After using a vacuum and a leaf blower I was able to get the carbon out of the vapor line. The leaf blower hooked to the fill tube and the vent line on the canister disconnected. I verified the line is clear and plenty of air blowing out and no more charcoal. I ran a borescope down the fill...
  11. T

    2008 Yukon gas tank issue.

    Not sure whats going on then. The tank is only half full.
  12. T

    2008 Yukon gas tank issue.

    Before I blew out the vapor line going to the EVAP canister from the fuel pump: When I disconnected the line from the EVAP canister gas dripped out of the canister. This might be normal? The EVAP canister and Solenoid are brand new.
  13. T

    2008 Yukon gas tank issue.

    I tried this using my leaf blower and some PVC fittings reduced down to fit the filler hole tight. I dropped the spare tire and disconnected the vent line from the EVAP canister. I blew out the line and several charcoal pellets came out. I connected everything back up and went to the gas...
  14. T

    I need to replace the fuel pump in my 2012 Yukon Denali with a Fuel System Control Module. I need to empty the gas tank?

    The pump has not failed yet. I need to drop the tank to blow out the vent line going between the EVAP canister and the tank. This truck is 11yrs old. My thinking is that if I have to drop the tank I may as well replace the pump while I'm there. It's a 26 gallon tank 1/2 full so about 13 gallons...
  15. T

    2008 Yukon gas tank issue.

    I have a 2012 Denali that started having the problem of fuel pump clicking off every few seconds. I replaced the EVAP canister and the solenoid valve. When I disconnected the vapor line going between the tank and canister I saw carbon pellets fall out of the line. I used a vacuum to try and suck...
  16. T

    I need to replace the fuel pump in my 2012 Yukon Denali with a Fuel System Control Module. I need to empty the gas tank?

    I need to drop the gas tank it's half full. I want to override the FSCM and pump the gas out using the fuel pump and the fuel rail valve. GMC decided to use a Fuel System Control Module and delete the fuel pump relay and fuse from the box. How do you remove the gas from the tank?

Forum statistics

Threads
129,472
Posts
1,816,375
Members
92,679
Latest member
xmen_1217

Latest posts

Top