Gas And Oil Servicing

How do you know when a Fuel Pump is going Bad

Allen Teal's image for:
"How do you know when a Fuel Pump is going Bad"
Image by: 

Without a fuel pump, a car will not run. With a bad fuel pump, it may start and run for a while, or it may not start at all. When the fuel pump is working right, you will not even know that you have one. However, if it fails, you will be left stuck on the side of the road about to have your wallet emptied for a repair bill.

Years ago, mechanical fuel pumps would cost you about $20 for the part and $15 or $20 to have it put on the car. Today, electric fuel pumps that reside inside the gas tank will cost you $200 or more for the pump and about the same to have it installed.

Avoid a total breakdown while traveling by learning the signs that signal a fuel pump is going bad.

If you can learn the warning signs that the fuel pump is starting to fail, you may be able to spare yourself the part about being stranded. In fact, if you are handy with tools, you may be able to save the labor bill, too. Weak fuel pumps are not always easy to diagnose. When they are first starting to fail, fuel pumps can often falter intermittently. They also tend to manifest the problem at highway speeds rather than at idle.

A bad fuel pump can mimic other mechanical problems.

The warning signs of a failing fuel pump are not hard to identify. The problem is that they can mimic other problems in the early stages. It is common for people to makes several lesser repairs before identifying a bad fuel pump. The expense of this big ticket repair scares most people away until there is no other choice.

Your engine will seem to miss at highway speeds.

A engine that misfires will cause the car to jerk occasionally while going along the highway. Frequently, the fuel pump will stutter for a mile or so two or three times and then run fine for the next 50 or more miles. This type of problem can be misdiagnosed as a bad spark plug or plug wire. In some cases, you will be told that a little moisture in your gas tank caused your fuel filter to act up. A mechanic may even persuade you to change the in-line filter if there is one or get a tune up.

Your car will lose power as you pull away from a standing stop.

You push down on the accelerator, and the car starts to go and suddenly seems like it is going to die. Immediately, it seems to restart and off you go. This type of problem is similar to an oxygen sensor failing. Since this is a quick but not always cheap fix, you may opt to give it a try. This same type of symptom can be caused by your smog control devices on the car. A final possibility is that the distributor or coil is not working properly. About 75% of the time, this will turn out to be the fuel pump.

You lose power at highway speeds especially when the car is climbing a hill or under a strain.

This problem is almost 100% of the time caused by a fuel system failure. The fuel filter is the first culprit. Once this is ruled out, the fuel pump is the next best bet. The difficulty here is that this type of failure can be intermittent, too. It may even improve for a short time if you change out an in-line filter.

Your car cranks when trying to start it, but it does not hit or start.

Two issues cause this problem. The first is the timing belt or chain has broken. Without a timing belt, your car will turn over, but will not start. Almost any mechanic will not have a problem figuring out which one it is. Most cars have an inspection plate to view the timing belt or chain. By taking a look inside, the mechanic can determine if the belt is alright. If it is, the problem is the fuel pump.

When several of these symptoms occur over a short period of time, you should seriously consider that it is the fuel pump. Taking early steps to have it replaced or replacing it yourself will save you frustration and possibly some cash.

More about this author: Allen Teal

From Around the Web