Hey everybody,
I’ve got a 1999 Honda Civic SI with 130,000 miles on it.
When the gas tank is full, it accelerates just fine and starts up right away. As long as my fuel tank meter stays above about half-full, the car drives the same way.
Once the needle starts dropping below half-full, the car begins turning over more times before it starts up, and at maybe a quarter-tank left it seems like my acceleration isn’t as great. When the tank gets close to empty (which I no longer allow it to do), it can take several tries to get the car started ? sometimes I have even wound up having to pump the gas pedal once or twice.
The car doesn’t exhibit this behavior all the time near E, but it gets more frequent and common the closer it gets to E.
One of the first times this started happening I continued to drive without refueling because I hadn’t realized what was going on. The needle was almost on E but the gas light had not come on yet. When I came out to my car after work that day, it would not start. At first it tried to turn over, then it just didn’t make any noise at all. The lights and everything still worked, so the battery wasn’t dead. I almost called a tow truck, then realized the gas was pretty much on E and I wondered if maybe my fuel light was broken and my tank was empty. I walked to a nearby gas station, bought a 2-gallon gas container and put it into my tank. The car started right up. I drove it to the gas station and filled it the rest of the way up with about 8 gallons of gas. I believe this car has an 11-gallon tank, meaning it should have still had at least part of a gallon left in it when it wouldn’t start.
The first time I took it to a mechanic, they replaced the fuel filters and gave it a tune-up. The second time, they weren’t able to find anything. I’ve just been keeping the needle above half-full ever since, and as long as I do that, the problem doesn’t happen.
Any ideas what this could be?
Your pump may be getting weak, or your EVAP system could be clogged…or both.
Your gas tank breaths in as gas is pumped out through a charcoal bed in a “charcoal canister”. If that somehow gets saturated ir clogged, a vacuum can develop in the airspace in your tank as gas is pumped out. Working against the vacuum can make it difficult for the pump to work and even cause premature pump failure.
My suggestion at this point is to just keep the tank over half full. But do not “top it off”. That can in some vehicles cause saturation of the charcoal bed.
Thanks for the info! Are there any additional symptoms I should be watching for that could tip me off that it’s time to do something about it? Maybe if it starts happening even above half-full?
If that starts you may want to have the fuel pressure in the line checked. It is possible that your pump has grown old and tired. We things that have grown old get tired.
If you notice this problem, stop and take off the gas cap. Does it make a hissing noise? If there was excess vacuum buildup due to the EVAP, the problem should go away. On the other hand, if the problem was a weak fuel pump, this won’t solve it. At least this might narrow it down.