I have a 99 lx m/t with 153xxx miles runs great, but when it gets down below 1/4 tank of gas, it takes noticable longer to start. Today when I was starting it it cycled like 10-12 times before I stopped, tried again and it cycled like 4 or 5 times before starting. It starts perfectly fine when full on gas. What could be causing this?

Also when driving/accelerating in higher rpms, the gas gauge goes down, but when stopped at a light idling, the needle will go up a little, and I was curious what cuases this?

 

Were you parked on an incline? The fuel systems in Civics suck, to say the least. The gas gauge bounces around like crazy, especially at lower levels. It does the same thing with me, which is why I never let my gas get below half anymore. At 150k miles I would definitely consider replacing the fuel filter, if you havent already.

When you accelerate, inertia kicks in. The fuel wants to stay in the same spot in the gas tank, so ends up shifting to the back of it. Since the fuel level sensor is in the front of the tank, it thinks the level is low. This will always happen when accelerating.

 

It was on fairly level ground, and still occurs in the garage (which is level). I only got the car ~3k mi ago (Aug 07), so I probably should get the fuel filter replaced, thing is I'm at college and don't have the tools, space, or time to do it myself. What are typical costs for it? I was thinking of getting some seafoam and running that through the gas tanks as well.

 

It happens with Civics.. Just don't run your gas down that far. 1/4 or more at all times

 

Running your tank to close to empty could hurt or kill your fuel pump since the gas with what lubes it. ur car will cut out and feel like its bogging down if your fuel filter is too dirty but i wouldnt get to stress over it