2003 Ford Mustang (3.8 L V6), Bucking

by Martin Solis
(San Antonio, TX USA)

I have a 2003 stock Ford Mustang (3.8L V6)and it runs fine 90% of the time. I take good care of it. I change the synthetic oil every 3K miles, I only use Shell or Chevron gasoline because of the gas additives, I use Lucas oil gas additives on occasion, I use Lucas Oil engine oil additive every oil change, I regularly replace the air and gas filter, I have a PCV enhancer to keep the engine internals cleaner, on and on and on...

I've worked to keep the car in good shape in the hopes of solving one troubling problem. At random times and without warning - the car runs rough. It bucks and sputters and the engine light will blink and at times the engine light will come on steady. No reason, just happens sometimes. The last time it happenned - I had a slight smell of gasoline in the cabin as I finally parked it. Most times, the bucking will go away if I park and turn off the engine then wait a minute to start it again. Some times, it's pretty stubborn and it just stops when it wants to regardless of what I do. I thought maybe my air conditioner compressor was going out making the engine work harder and kicking it out of timing - nope. I thought it might be electrical - but a $100 diagnostic showed no problems at all. The garage told me I need to come in when the problem is actually occurring in order to find the problem, but since it occurs randomly and always at times where I'm no where close to the garage - I fear that will never happen.

Is there a history of this problem with 2003 Mustangs? What mysterious thing could keep happening to this car. It happens at random times, but I'd guesstimate it happens once every 2 to 3 months.

What the heck?

Steve Says,

Hi, Martin. Thanks for asking me your question. The first thing you should do is find a good repair shop that can read the codes on your car. If the check engine light came on then there will be codes set. The fact that this shop that you took it to said they didn't see any codes tells me that they were just ripping you off. Any time your check engine light comes on it sets a code and this code will help you to track down this problem.

In fact, if you want to spend a little money to get your own code reader (available at most any good auto parts store) you can read the code yourself, then come back to my website and search for the code using my search bar to see what might be causing it. This way you can save yourself some money and you will know what the code is before you take it in to have it repaired.

There are many things that can be causing your problem. Everything from the fuel pump to an ignition coil. I can tell you that the fact that your check engine light was blinking means that your car was misfiring. That is generally the cause of the light blinking. The code that is set should tell you which cylinder is misfiring.

I hope this has helped. Good luck finding a good repair shop.