Reader Question Dear Austin,
In the midst of a Google search for “How can I tell if my fuel pump is bad?” I came across your site – specifically, Rocky’s question that you answered on Feb. 19th.
“About a year ago my car stalled and I had to replace the fuel pump.
Recently, my car has been showing similar signs of the same problem ( ie. not getting up to speed when I press down on pedal, not starting right away, feeling jerky while driving )”
My 97 Dodge Intrepid at 117k miles is showing these same symptoms. It’s never stalled, however, and the symptoms only seem to occur at certain points in my commute – which I will outline for you shortly – and only at certain times of the year: late Fall and early Spring.
Like Rocky, I will also admit to keeping the fuel at less-than-half at times. Typically I fill up every other Friday (payday!) and the fluctuations in my driving habits sometimes take the level down to the Low Fuel indicator. The amount of fuel in the tank does not seem to affect when the symptoms occur, though.
Anyway, here’s a brief outline of my commute:
-10 or so blocks of stop ‘n go traffic to the interstate
– then 10-ish miles of interstate driving
– then get off the interstate on a downhill ramp to a stoplight, which is almost always red when I get there. While stopped at this light, I sometimes have a rough idle (lately, it’s been every day).
This makes me think gravity is acting on sludge, or something. But when I hear this rough idle, I have learned that I will soon be experiencing the jerkiness and unresponsiveness to the gas pedal that Rocky mentioned.
– The light turns green, I make a left and go. Slowly, and jerkily. I pump the gas somewhat frantically to get up a slight hill to another (always red) stoplight. Magically the idle is back to normal here, and remains so for the next 5 miles to work.
That’s the one scenario that has happened so many times that I worry about it every time. Sometimes it’ll happen when I have my cruise on, on a long trip somewhere, on flat terrain.
Sometimes it’ll happen at every other stoplight for a whole day, then not happen again for a week.
And it never happens when the temp is over 70 or under 20.
Sound like a fuel pump problem to you?
Howdy there Randy,
I think I would have your spark plug wires inspected…if not replaced. From what you tell me, I would suspect you have a bad spark plug wire causing an engine misfire. If the wires have more than 60K miles on them….they are due for replacement anyway as maintenance. Would also be a good idea to replace the spark plugs at the same time.
You can sometimes spray a light mist of soapy water solution on the spark plug wires with the engine running…if the wire is bad it will ground out and cause the engine to misfire or you can sometimes see an actual spark jumping out of the wire like you see here in my video. (sorry there is no sound in the video)