Running empty too often, can damage a fuel pump. Most modern fuel pumps are submerged in gasoline in the gas tank. The fuel is used to keep the fuel pump cool. So if you have no fuel in the gas tank, the fuel pump will overheat eventually and fail.

 

So engine breaking is not costing me any more fuel than coasting in neutral while braking...??

 

thank you!!! I've always been taught that the fuel around the pump was also used to cool the unit... I took up engine performance I and II in a Junior College a long time ago. But, I know that some, if not most of the material still lodged in my head, are probably outdated and obsolete. Cars were way simpler back in the days.

 

Actually, you use MORE fuel coasting in neutral. As I said, the ECU will turn the inujectors back on to keep the enine from stalling. As long as coasting in gear, the engine isn't going to stall, and the ECU will keep the ijectors de-energized until RPMs fall below some point.

bill

 

I have just read that modern engines equipped with an overrun fuel shutoff, like the Z, should not experience any increase in fuel consumption during engine braking. It actually does "shut off" the injectors but not completely...It has to feed the chamber enough fuel to ignite in the compression phase, but not as much as it would when your foot is on the pedal. Your engine still needs fuel in each cycle, what the shutoff does is save you from burning fuel unnecessarily... You have broadened my knowledge of modern IC engines, bill. However, I still believe that running your car out of gas is not good.

 

350+MPT!? My car always reads ~285 DTE when I fill it up to full. It feels like it only lasts a couple hundred miles too. I average 18MPG.

 

yeah mine says 280 left on a fill up...says i get 17-18mpg...and i dont always drive hard either :/

 

I thought i was the only one who was only getting ~16 gallons on a --- DTE fill up...

3 gallon reserve sounds like a lot.

 

Im sorry to say guys but the Z only has a 16 gallon tank. 285 DTE on fill up.
cost me 72 dollars to fill up the other day and i actually hit 16 gallons.

 

You must not have read this thread.

Or the manual.

Or maybe by "Z" you meant the 240Z?

 

the 350z holds 20.2 US Gal. of fuel

 

Right answer

bill

 

If yu have no fuel in the tank, the engine shuts off, and the fuel pump shuts off.

bill

 

I usually do 300 miles on a full tank and average 18 miles or a little more, but under 19 I think. Now that the gas prices don't make any sens I don't even bother filling it up anymore. I also started having some problems with my fuel gauge. She drops faster than she should. I just know it because I have been driving the car enough to assume that theory myself. Anyways, any help would be appreciated because I'm gonna have a new tranny put in soon and if I could get help to figure out what the problem is I would less likely get ripped off with a scam because of not knowing enough on the issue if I decide to fix the problem when I get the new tranny put in. Thx

 

Sometimes when I put a full tank in (yes topping off also) the gauge reads just under Full. Any idea? Related?

 

It's related to the float issue, you'll want to get that looked at.