Originally Posted by jimfife
New to this forum; sorry if old Question. We are new to a 40k mi '04 Chevy / '05 Roadtrek 190 Versitile. Recently it has lost power and stalled a few times on long but mild-uphill grades @ 55 to 65 MPH. Altitudes less than 5k ft. Easy restart after stopping, then runs normally. Weather was HOT but oil, temp & voltage gages normal before stall. Was in cruise control when power losses occurred. Is this a known prob? Is it related to the fact that the gas-tank is very difficult to fill: most gas pumps' minimum flow rates cause pump to auto shut-off, requires difficult manual minimum pump squeeze or shut-off/squeeze/shutoff etc. 100 times or more. Are both issues a tank venting prob? Are these Roadtrek modification issues, or a Chevy van prob? Any ideas, please.
It could be venting, but not particularly likely. That is easy to test by leaving the cap loose when it starts to act up. Hot weather and high load issues often are fuel pressure related. Fuel pump/fuel filter could be getting weak. You could be getting vapor lock from fuel boiling in the fuel lines near hot areas. Ethanol laced fuels are much more likely to vapor lock than pure gasoline. At 40K, I think I would start with the fuel filter, as it is cheap and easy compared to other things, and is due anyway. Then move on to a fuel pressure test. GM products are also prone to failure of the crank position sensor, which will give you the symptoms you see. It will suddenly quit, but restart and run fine. MOST of time, but not always, they will set a "check engine" code from a crank sensor, as well as problems with other electrical components.