dirty intake filter
clogged fuel injectors (rough idle?)
bad fuel regulator (do you smell gas?)
heavy foot ( do you speed?)
i owned a Dodge neen ( manual) for 4 years and put 100,000 miles on it this car is great on gas and gave me no problems besides blown head gasket at 50,000 miles.
use regular unleaded gas never use super for a neon (2.0 base)bad for your timing
Try bad EGR valve, oxygen sensor, (these would cause your check engine light to go on). Also you may want to adjust your driving habits. If you "jackrabbit" from red lights/stop signs, or you go short distances stop and go, this can affect the gas mileage. Or try changing your gas station. You may need a tune-up, spark plugs, or oil change. Your PCV valve may be sticking, your air filter may need changing. Try fuel injector cleaner with your next fill up. NEVER run the car low on gas(as soon as it "dings", fill it up!) and NEVER push the fuel nozzle past the 1st click at the gas station.
Another leading cause of bad gas mileage with Neons is driving all the time with fan switch turned to the left on A/C. As soon as you turn it that way you cut your mileage in half. Even with the temp turned up it bogs down the engine. Also, don't turn on your headlights until you need to. Many people run their light all of the time for safety. This makes the engine work harder. The daytime running lights are enough.
It depends on what you consider poor gas mileage and what kind of driving you do. If you are in the city a lot then anything above 20mpg is acceptable, if you are on the highway a lot then anything above about 26mpg is acceptable. This is mentioned on the window sticker right below the EPA rating. All cars have a range of acceptable fuel economy and none are guaranteed to get the EPA estimated number that is is in big print.
I found my gas milage severely diminishing in my 2004 SXT. Repacing the spark plugs and wires did the trick (the no. 3 wire was not making a good connection, fouling the plug and causing a sparatic sputter). just to play it safe, I also replaced the PCV valve, did an oil change (I was about 500 miles overdue), added injector clean to my next tank, and put a K&N intake system on (I was going to replace just the filter, but then decided 'why not?'). The neon gets the best gas mileage it ever has now, and she sound beautiful, too.
Also, to avoid any repeating problems soon - don't go cheap on plugs or wires. You will just have to replace them sooner. I recomend the new Bosch Iridium plugs (about 10 bucks a plug) and BWD Premium 8mm wires (bout 60 bucks for a set of four).
If you notice your coil pack looks fouled up when you replace the wires, that could be your cause, too. so that is another area the problem could occur.
None cause the earth is only 25,000 miles or so in circumference.
16000 kilometers has 9941.939076 miles = 9942 miles approx
There are 5280 feet in one mile. Therefore, 16000 feet is equal to 16000/5280 = 3.03 recurring (that is, 3.030303...) miles.
There are 1760 yards in one mile. Therefore, 16000 yards is equal to 16000/1760 = 9.09 recurring (that is, 9.090909...) miles.
Answer: 16000 km = 9,941.939 mi.
There are 1609.344 metres in one mile. Therefore, rounded to two decimal places, 16000 metres is equal to 16000/1609.344 = 9.94 miles.
probably an emission sensor take it in and get tested