Running on Empty

The most current issue of “Motor” magazine came today and it contained a article revelant to this discussion. The author was describing the new smoke machines (used to detect evap leaks). The revelant part to this discussion is that today some cars are using a system called Natural Vacuum Leak Detection (instead of a seperate leak detection pump) the theory is that as “the fuel cools,the system naturally is drawn into vacuum”. So negative pressure does exist in the gas tank and this naturally occuring phenomena is used in the leak detection process.

Good article on Chrysler No-crank No starts caused by static electricity locking up the Wireless Control Module (keyless entry) but that discussion is for another thread.

I think we’re simply going to have to agree that we disagree on this one. But I will ask one more question: if the void in a gas tank does not contain gas vapors surrounded by air, which is 22% oxygen, what does it contain?

Am I showing my age…or what ?

Nacho cheese sauce.

This question has gone around this web site several times over the years, and I’ve been chided, because I fully admit that I tend to run my car down until the fuel light comes on before getting gas. I have been doing this for many years, and never have I had a failed fuel pump or any other problem. This is on a variety of cars from the 1980s onward.

First, the idea of water and crud accumulating in the bottom of the tank, while true that it does, it’s also true that the fuel pickup is near the bottom all the time. If the water and crud gets deep enough to reach that intake, you have trouble whether the tank is full or not. As long as you aren’t running it out of fuel, it seems to not cause any problems. And, I have only run out of fuel once since about 1976, and that was on a motorcycle on a Sunday when I could not find an open gas station.

I have had access to fuel tanks in a landfill collection site and have taken a look or two. Fuel pumps are near but not at the bottom of a tank but the fuel pickup is via a filter sock.

If your fuel tank level is a concern, then your owner’s manual will say so. Believe the car makers who have a stake in your satisfaction. One thing not mentioned is that agitation of gasoline as when driving increases vapor pressure. JJ, you worry too much about imagined situations. Did anyone who replied state a roadside stoppage due to items that you posted? No? Drive on!

Tom and Ray must be diplomatic and give some regard to their followers views.