2007 GMC Sierra 4.8 Vortec. Question Here.: There is a restriction between the gas fill goose neck and the tank making it accept gas but very slow. It takes about 10 minutes to put in 20 litres of fuel. Can I fix this myself.
I have been told that if I shove a garden hose in the filler neck I can force the restriction into the tank.
Answer: First off, if there is something in the filler tube, you probably wont be able to push it through because there is a check ball at the tank opening. If you were to get it through, you run the risk of whatever it is plugging up the fuel pump intake screen and causing the truck to run bad because of a fuel restriction, or the truck won't start some time. If someone put something in the filler tube, use a flash light to look down the tube to see if you can see it and maybe pull it out with a coat hanger with a bend on the end. But more likely your problem is with a sticking EVAP vent valve. When this fails it does not allow the tank to vent when filling and causes the trouble you are having. Usually it is accompanied by a check engine light and scan code of P0446 or P0449, but not always. Most of the large national parts store chains can scan the computer for free. If this was bad, it may be under the factory or emissions warranty coverage.
GMC Sierra Low Gear Problem
2000 Sierra 1500. Engine Size : 5.3
Question: transmission will not kick out of the trailer tow gear.
Do you mean it won't downshift from 4th gear when accelerating at highway speeds?
The transmission is in the tow-haul position, it won't switch back to the regular drive 3 2 1 position. The tow-haul button is stuck on most of the time: it kicks in and out.
This problem should be electrical. The Powertrain (PCM) and Body Control (BCM) control the tow-haul mode and shift patterns. Shifting is different in this mode. If it will not disengage, it could just be the switch is bad. It could also be a problem in the communication line between the two computers. A mechanic needs to scan for computer codes and look at live scanner data to determine what is happening with your truck. There are no common causes for this that I have seen.