Lack of Accident Evidence Can Alter the Truth


Question: I was recently rear-ended when I changed lanes. Luckily nobody was hurt, but the police found me at fault. When I attempted to find out why, the police officer said I caused the accident by making an unlawful lane change.

I believe the other driver was speeding, but the police said there was no evidence of his speeding. This seems crazy to me. How can I be at fault?


Answer: Investigations of lane-change accidents often are difficult because of a lack of obvious evidence. Also, police are reluctant to spend much time looking into an accident in which no injuries occurred.


Under state law, you are entitled to make a lane change based on the assumption that other vehicles behind you are driving at a legal speed, said Bill Edmonds, a private accident investigator and longtime accident specialist with the Los Angeles County Sheriff’s Department.

But hasty police investigations often disregard this fundamental premise, looking for a single action that a driver took that directly led to the accident. This action is known as the primary collision factor. In a lane-change accident, it’s far easier to blame the driver changing lanes.

“Often, the easiest one to prove is not the correct cause,” Edmonds said.

The same type of investigation mistake typically occurs in accidents when drivers make turns and enter intersections from stop signs. They misjudge the distance of oncoming vehicles because the vehicles are traveling at illegal speeds.

Police often consider investigating non-injury accidents as drudgery that serves only the interests of the insurance industry. They typically do not take skid-mark measurements, make only cursory examinations of accident damage on vehicles and make no effort to interview witnesses. Their conclusions usually are based on driver statements.

There isn’t much you can do about it. Most police officers and police investigators refuse to reconsider their conclusions after their report is filed.

Q: I have twice had the idle air control assembly replaced under warranty on my 1999 Toyota RAV4, which has about 30,000 miles on it.


Dealership representatives have informed me on both visits that it’s a known problem that carbon builds up on the part, causing it to malfunction.

My warranty expires in June and I am concerned that the part will fail again, costing me $300 each time. Based on my experience, the part will need to be replaced every 15,000 miles. What can you suggest?


A: Toyota has not issued any technical service bulletins on that problem, so it is not a well-recognized issue by the company itself. Nonetheless, mechanics already may have figured out that the part has a higher-than-normal failure rate, and that is what they passed on to you.

The idle air control assembly is attached to the engine’s throttle body, which is the main element of the fuel injection system. The device has a solenoid-operated valve that regulates the amount of air going through the throttle body, thereby controlling the engine’s idle speed, according to Alldata, a major publisher of automotive repair and diagnostic information.

The part, an item typically sold only by dealers, has a list price of $198.54 and should take about 11/2 hours of labor to replace, according to the Alldata rate book. At a standard $60-an-hour rate, that would add up to $90 for labor. So, the $300 price tag you mention is right on the mark of what you are looking at if the part goes bad again.

Eventually, aftermarket manufacturers will see a big business in making the part, if indeed RAV4s are dying all over the place because of a defect. That should bring the price down on the part. But that doesn’t help in the near term.


It is not unusual for fuel injection throttle bodies or various parts associated with the throttle body to become contaminated with carbon buildup. In general, there are procedures for cleaning the carbon without having to replace the parts, and this may be possible for the part that has caused you problems.

Your letter suggests Toyota customer service has not responded to repeated efforts by you to get some clarification about the future warranty coverage on the part. But you should keep trying. Toyota recently extended the warranty for sludge damage on its engines after customers raised a stink about what they considered a defect.

In general, dealerships will cover certain parts after warranty if you have established that the car was being repaired for a known condition during the warranty period. This may help for the next replacement, though at some point you are clearly going to be on your own.


Ralph Vartabedian cannot answer mail personally but responds in this column to automotive questions of general interest. Please do not telephone. Write to Your Wheels, Business Section, Los Angeles Times, 202 W. 1st St., Los Angeles, CA 90012. E-mail: