Q: My sister totaled her 2008 Hyundai Sonata recently. It was a sunny, 70-degree, clear day. She was stopped at a stoplight behind a delivery truck. The light turned green and they both were taking off. My sister said that she hardly touched the accelerator and her car lurched forward, smashing into the delivery truck. She said this was the third time her car had done that and that she didn't tell me about them because she didn't hit anything. I told the insurance adjuster about it. He looked at the floor mat and it was in place so he said he would look into it. I have not heard from him. Have you heard of this particular car doing anything like that?

A: I checked nearly 150 service bulletins and recalls issued by Hyundai as well as recalls and investigations listed on the NHTSA's "safercar.com" web page, and found nothing. I did find several dozen individual complaints from car owners on various Hyundai forums.

All of which means that if there is/was an issue at the time of the crash, you'll have to find it yourselves. If the airbag deployed there will be specific "event" information stored in the EDR — event data recorder. Under certain crash or near-crash circumstances, the EDR will store about 30 seconds' worth of vehicle dynamics and safety system data leading up to and including the "event." It will show whether seatbelts were fastened, how far the gas and/or brake pedal were depressed and vehicle speed.

Ask the insurance adjuster to have this information downloaded from the EDR. If the insurance company or carmaker won't do this, you may need to hire an attorney/professional crash investigator to download this data.

But be prepared. Believe me, I'm sensitive to what your sister believes happened but it is entirely possible the "event" was caused by driver error. Taking into account she had not reported any previous issues, absent any confirming data or physical evidence it will be very difficult to prove unintended acceleration.

Are you famliiar with the term "cognitive dissonance"? In simple terms it describes the discomfort we feel when what we believe happened may not actually have happened. From my experience in performing "vehicle autopsies" — post-crash mechanical/electronic inspections — many drivers want to find blame in the vehicle for the crash, not themselves. As time passes, this belief often solidifies, helping relieve them of responsibility. It's human nature.

Am I being too heavy-handed? Perhaps. But in the dozens and dozens of crashed vehicles I inspected to look for mechanical or electronic problems that contributed to or caused the crash, I found only one.

Q: The backup camera on my 2011 Toyota RAV4 has been giving me problems. There was a delay during damp conditions but it would come on in a few seconds. Now it is just a blue screen that flickers occasionally and then shuts off. Any ideas that can be done without going to a dealer?

A: Here's a simple one — check the right side-view mirror, then look back over your shoulder. Throughout automotive history this has been the accepted method of checking behind the car before backing up.

The only DIY troubleshooting I can suggest is to check the electrical connections for the camera. If your vehicle is equipped with the external spare tire, remove the spare and the external plastic garnish on the outside of the rear door to gain access. It's a bit more involved if there's no external spare.

– Paul Brand. 'New engines are cheaper than new wives' – Ray Magliozzi (Car Talk), answering an unrelated question.

"So, the moral of the story is to make sure you change oil on schedule, but never tell your wife to make sure it gets done!"

Paul Brand is the author of "How to Repair Your Car" and "How to Repair Your Truck and SUV," published by Motorbooks.