Knocking noise coming from the fuel tank area.

When it starts to act up, take off the fuel cap and see what happens. Check the computer to see if there are any codes. Possible weak fuel pump. Check pressure with a gauge. Check fuel filter. Squeak noises are common. Look for the area the noise comes from and isolate the squeak.

You shouldn't have to pump the gas for a fuel injected vehicle to start. Where is the very loud noise coming from? If it's from the gas tank, then it very well could be the fuel pump beginning to fail. Sometimes you get no warning. You just get stranded. A mechanic would likely check your fuel pressure with a gauge.

ok on todays automobiles the gas cap does more than just seal the gas tank. Now they run a return line to the tank. this does 2 things. it returns un used fuel and vapors back to the tank , and it pressurizes the tank to help improve the fuel pump.

Now as it is possible running without the gas cap may cause problems I am not 100 % positive that is your only problem.

It sound like the knock sensor is detecting the knock you mentioned and is trying to retard the timing to fix it . In doing so it has retarded it to far causing the engine to loose power and eventually stall. I would first replace the gas cap. then run a good gas additive to a full tank of gas to clean out any water and dirt that may have gotten into the tank while the cap was off. now the issue of the knock as you described. is it a knock or a ping? A knocking sound is loud metallic hammering noise. a ping is a ting not very loud. if it is a loud metallic sound I would have a reputable mechanic check it soon, as it could be a serious issue. Ping can be caused by bad or weak gas or cheap low octane gas. I would run a mid grade gas in it and see if it fixed the issue.

it may be that u are leaking gas from the fuel line. follow it from tank to the engine and look for a leak. do this asap as it is fire hazard

sounds like your vent is plugged up or broken, so when you drive you create a vacuum and the fuel tank is being pulled in, thus the banging I just had a car with this issue, and I had to pull the tank out of the car and had to the show the customer before he would believe me, but seeing IS believing as they say. When you shut off the engine the vacuum decays and thus the tank reverses its process. Try driving your car with the fuel cap off and see if the noise goes away. That will prove it!
(also)- small leak in the tank
and finally try changing the gas cap itself
let me know
thanks
~Dave RockAuto Parts Catalog these folks are the best around for auto parts and believe me when i say you get your parts (if needed) before they say they will be there been there my friend.
if this does not work let me know and we will get this fixed i have had every problem with these luminas you can ever think of this is a fact lol and some are and can be nightmares but great vehicles no matter what anybody tells you i have owned them and worked on these for years now and this is 2014 so take it from there i have owned a 1999,98,97
~Dave

Ok 1 did you buy a brand new pump. 2 did it come with a replacement wiring harness. 3 if either 1 of those answers are no go buy a brand new pump with harness. If yes to both you got a bad pump.

The problem you are discribing could well be the impending failure of the fuel pump I am assuming that this is a late model fuel injected car . The noise is transfered by the fuel in the tank . Have a tech check and make sure you have only a small amount of fuel in the tank when getting the pump replaced as the gas tank must be removed in order to replace the pump . Hope this is some help
Regards

The bad gas cap is related to the evaporative emissions what happens is the gas that is not used in the engine return to the tank via the 2nd hose. The tank is pressurized very lightly by this and a sensor detects whether or not the air escapes. So if the cap is loose or there is a leak in a hose the code will set. Since you also have a leak I would start there first. The straps most likely are not cutting the tank the epa would have a fit. Most likely the the gas is coming from above the tank and working its way down the straps. Lowering the fuel tank requirs raising the car quite high. If you are able to inspect the area and reach it I think the leak would be in the gas lines above the tank. Or from the filler tubes when you fill with gas. If you can see the gas leak but are unable to reach it take it to a shop. This may fix the light if not a shop with a (smoke machine) will pump smoke into the system and search for air leaks that way. Good luck .

if its coming from the gas tank area the only thing i can think of would be the fuel pump..they make a little humming sound, but if its making a howling sound it might be going bad. does this help?

First thing i would try...... ISOHEET, Red bottle..... allows water to be mixed into the fuel and be burnt out of the tank.
get a good qaulity fuel injection cleaner, if you can locate the brand MALCO, i found it quite succesful..... and go with a full tank of premium fuel such as ammoco or shell......do not use yellow bottle of heet