Why did my check engine light switch on?

John Paul, aka “the Car Doctor,’’ answers readers’ car-related questions.
John Paul, aka “the Car Doctor,’’ answers readers’ car-related questions.

Q. In December we had some heavy rain and I stupidly left the passenger side window open on my truck. The interior carpets and seats were soaked and the check engine light came on. After a few days of wet vacuuming the truck the interior dried out and the check engine light went out. What do you think happened?

A. Your truck like all vehicles today are rolling computers, more than likely one of the computers got wet, which caused the check engine light. As the computer and it connections dried out, the circuit returned to normal operation. Even though the truck dried out it still may be worth lifting part of the carpet to insure that it isn’t damp and growing mold and mildew.


Q. I purchased a used 2013 Buick Enclave from a large used car dealer. This Enclave only has 20,000 miles on it but it was a former lease/rental car. The car only had 23,000 miles on it when I purchased it. When I started to drive it I noticed it had a slight pull to the left. The dealer has since aligned the car, rotated and balanced the tires but now there is a vibration. Any ideas?

A. It is possible that the tires were not balanced correctly and that would be the first place to look. The second issue is the wheels on this model are very sensitive or over-tightening. If the wheels are not tightened properly there can be a vibration between 58 and 75 miles per hour. The proper method for tighten these wheels (and any wheel in my opinion) is to tighten it by hand using a crisscross pattern and then finish it off with a torque wrench set to the manufacturers specification.

Q. I own a 2002 Lexus SC430 which has only 47,012 miles. It has always been garaged, well-maintained and is in beautiful condition. It is smooth riding, runs very well and I really enjoy driving it in the nice weather with the roof down. My repair shop suggests I consider replacing the timing belt (usually done at 90,000 miles). The water pump and all other belts would also be replaced for a total cost of over $1000. I’d like to believe that “If it ain’t broke, don’t fix it.’’ But I do love this car and want to keep it forever! Do you recommend these replacements be made at this time?


A. Timing belts generally get replaced based on both time and mileage. Failure to replace a timing belt on some model cars can result in catastrophic engine damage. In your vehicle Lexus recommends replacing the timing belt at 90,000 miles of 72 months whichever comes first. Since your car is nearly 14 years old it is overdue and worth the money to keep the car trouble free. .

Q. What do you know about a device that allows you to turn your car into a mobile hotspot? The device that I have seen is called Vinli. Any information would be appreciated.

A. I have not tried this device yet, but may in the near future. It has some interesting features in addition to the mobile hotspot. You can track mileage, report your car stolen as well as track its location. There are also service related apps that allow you to schedule repairs as well as a novice driver feature to track your teen driver. The device plugs into the on board computer (OBD) port that is in nearly every car and then can link to a smart phone. I would say to date this is the most comprehensive “add-on’’ device I have seen to date. One minor concern that I have will all of these OBD dongles is that the computer ports were never designed for this type of high-speed two way communication. In the past I have seen some of this type of product cause check-engine light issues and in some cars drivability problems. I plan to try Vinli in the near future.

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