Consumers have an important role to play in helping regulators and automakers find and correct problems in their cars. Many problems, such as the Toyota unintended acceleration incidents, are so rare that car owners are the only ones who have actually experienced the problem.

So it’s important when consumers file complaints that those submissions be as descriptive and accurate as possible. In doing our own research on unintended acceleration in Toyotas, that’s not what we found.

Here’s a typical example (on a 2005 Ford F-150) submitted to the National Highway Traffic Safety Administration (NHTSA) and transcribed for entry into the complaints database:

“The contact stated while applying brake pressure at low speed through a parking lot, the vehicle lurched forward into an embankment without warning. No injuries or damage was sustained. The police was not alerted. The vehicle was driven to the dealer who was unable to duplicate the problem. The manufacturer was not contacted. The consumer stated the truck was in park, when he applied the brake to it in gear, the pedal became stuck. “

In contrast, this example (on a 2010 Toyota Camry) is among the most specific, actionable complaints we’ve found yet in the NHTSA database, but even it isn’t perfect:

“I am requesting that DOT NHTSA investigate the driver’s contribution to unintended acceleration (UA) and Toyota’s accelerator/brake pedal designs that make it possible. I was driving a rented Toyota Camry in a parking lot. I applied the brake and instead of slowing down the vehicle began to gain speed. I pressed harder on the brake and it accelerated. The harder I tried to stop the car, the faster it went. I took my foot off the brake for a moment and the vehicle stopped accelerating. I believe that my foot was on both the brake and the accelerator pedals. I measured the distance between the brake and the accelerator and found that it was only 1.5 inches. My vehicle a GM Acadia is 2.5 inches. This made me think that the tops of the two pedals are too close together. I managed to find 6 different Toyota models, including the Prius, and they averaged 1.5 inches between the tops of the brake and the accelerator pedals. I measure competitive vehicles and found they averaged 2.2 inches. Something is wrong with the Toyota designs – they are too close together. I have continued to investigate unintended acceleration and have collected a significant amount of data that supports the fact that the driver is a major cause of UA and that some vehicle designs make it possible…. Please formally investigate.”

Those experts agreed with our own; what’s needed is more detail. Nevertheless, be as brief as possible, providing very specific descriptions of what happened, rather than long, rambling stories.

What to include

Your vehicle’s vehicle identification number (VIN). The Web form has a space for this, but not all consumers include it. This can help investigators pinpoint where and when your car was built and what major options it may have. These details can help investigators group your complaint appropriately with others whose cars are most similar.
Your name and contact info, so investigators can get back to you with questions or for more details later, if needed.
The mileage on your car, and whether you bought it new or used.
Any maintenance history that might be relevant. (Oil changes are probably only relevant for complete engine failures, for example.)
What you did, and how the car responded, in chronological order, including your speed, what gear you were in, whether you applied the brakes or turned, and how hard.
Any steps you took to isolate the problem, such as checking for floor mats. Be specific about what you did and how you did it.
Corroborating evidence, such as a summary of the factual findings in a police report, if there was an accident, or a mechanic’s determination of any repair work needed afterwards.
Other details that can often be relevant include whether this was a routine trip or someplace you’ve never gone before, weather, traffic, and road conditions, and your location (urban, rural, intersection, parking lot, etc.).
A clear description of how you think the car failed to perform, preferably in the first sentence.
Any aftermarket equipment, such as accessory pedals, that may be relevant.

What not to include

Your feelings. Sometimes your emotional state before an accident or near miss occurs can be relevant. Sometimes your emotional state in the aftermath of such an incident is relevant, as you are examining the evidence of what happened. Almost everyone will be fearful and stressed during the incident. Investigators will assume that. But unless you were unusually calm and composed under stress, it won’t set your complaint apart from any others or shed any light on how such a fault could have happened.
Why this incident makes you angry. Chances are, if it didn’t upset you, you wouldn’t be filing a complaint.
Your destination, why you were making the trip, passengers in the car, and obstacles you were afraid of hitting are usually not. They don’t involve what happened to your car (unless you hit them). If a passenger has an observation relevant to the incident, include them.
Spelling errors.Researchers often have to use text searches to find specific problems. If key words aren’t spelled correctly, your complaint may never be found.
Multiple problems in the same complaint. If you have two different problems, file each complaint separately. That way they can both be categorized accurately.