Just to start off, I have the gas gauge issue that some people have here where it will show that I have 1/2-3/4 of gas in my tank but is actually 1/4 to empty. I haven't had the chance to clean the tank sensor using the DYI instructions so I fill my tank and reset my odometer. Once I'm at around 310 miles, I fill up to around 15-17 gallons and assume I have approximately 50-70 miles I could have driven based on our 20 gallon tank.

So to my story, we're driving home from a long road trip and assume we would get at least 20+ MPG (usually get 17-20 city/hwy). I planned to fill up at around 320 miles to be safe, but once we hit 305 miles the engine started to hesitate the way it would when it is close to empty. I have experienced near empty gas in 3 occasions and know the feeling. I take the next exit with 3-4 blocks to the closest gas station while still feeling the engine hesitation. I fill up the tank to about only 14-15 gallons meaning I had plenty to make it to at least 320. So what would cause my car to act this way with more than enough gas to go? I was going about 70 MPH on a leveled freeway and my engine temps were OK. Before the trip, I had an oil change and my radiator replaced w/flush.

Sorry for the long winded details and thanks for taking the time to read this. Please help.

Misc. info:
140,000+ miles
2005 G35 sedan
5w30 blend
replaced plugs and belts in 2012

Thanks.

 

I didn't read it all... TL;dr. But we have 16 gal till fuel light, 18 till the ticker hits empty on the guage, and 20 gallons of possible space to fill with fuel. Does that help you?

 

fuel pump? Does the fuel pump make more noise than normal? There is a gauge you can use to see how much pressure it's building in the fuel system.

Just general things to check:
Clean air filter?
Any stored codes in the ECU? (like MAF sensor out of range, 02 sensor out of range, etc)
Did you use good fuel? You may have just had bad gas.

I have felt the same feeling in the car when i'm low on gas and have to stop quickly. It goes away on level ground though. Guess I haven't been as empty as you.

I typically can go almost 450 miles straight highway though. I average 26-27 on the highway going 70-75.

 

I get 400+ miles out of every tank, but from what I have read, it is not the norm.

 

Try running a couple of tanks of gas with SeaFoam or Lucas Fuel Cleaner added to the tank. It might clean your tank sensors and the fuel injectors. My seat of the pants dyno shows better throttle response when I use either of those products.

 

Urbanengineer, didn't answer my question, but thanks.

miltoda, I haven't noticed an increase in noise, but I will look into checking the pressure in the fuel system. I do need to replace my air filter that has been sitting on my shelf, but it would seem odd that it would be the cause for little response from the gas peddle. I had my OBD scanner connected the entire trip so I could monitor any changes during the trip and no codes came up. I only use premium from Chevron so hopefully no bad gas. I calculated my MPG for the last tank and it came to approximately 21-22 MPG. I've never seen higher than 22 so you must have a nice commute.

PAIXAO, I usually average 340-360 miles until my "E" light would turn on. Since my tank sensor isn't functioning correctly, it is more of a guessing game now.

Bassman, I forgot to add some Lucas before my trip and I usually notice some improvement when using it. I will be more proactive with using it to see if it solves my response issue.

Thanks to everyone for their responses. I will provide an update if I have one.