Directional tires shouldn’t be crossed when rotated

Q. In a recent article, you had a Q&A about tire rotations. While I agree with everything you said, I believe you forgot one important comment. What about car owners who have unidirectional tires? They can’t cross tires. Their tires must remain on the same side and can only go front to back and back to front during rotations.

A. Thank you for your response and your important clarification.

While my focus was on rotating normal run-of-the-mill passenger tires (and the rotation differences between front-, rear- and all-wheel drive vehicles), I should have made mention that when you have directional tires on your car, you can only rotate front to back.

Thanks for catching this so we could call attention to it here!

Online research

We had a 2005 Chevrolet Cobalt towed in the other day because it would not start and, in fact, had to be jump started several times leading up to that point. We charged the battery but quickly determined the battery was bad and needed to be replaced.

After replacing the battery the car started and ran fine but on a test drive we noted the check engine light was on and the car was stuck in second gear, basically a “limp in mode.” A conversation with the customer indicated no previous problems like this had occurred.

A computer diagnostic pointed to a communication problem with the transmission control module, and possibly a bad module. Since there had been no previous problems with this car, it seemed something just wasn’t adding up. We started an online investigation into possible known problems with this system and discovered a fair amount of hits where the transmission control module needed to be replaced after charging the battery or multiple jump starts.

Now we were on the trail, and found an obscure Internet post about the module losing its ground connection after multiple jump starts. The remedy was to run a new ground connection to the transmission control module. The control module was fairly accessible so it made this correction an inexpensive repair.

The ground connection was made and, just like that, we had communication between the computers. The check engine light went out and the transmission shifted perfectly. In many cases spending some time at the computer researching can save a lot of time, money and frustration.

Ÿ Douglas Automotive is at 312 S. Hager Ave., Barrington, (847) 381-0454, and 123 Virginia Road, Crystal Lake, (815) 356-0440. For information, visit douglasautomotive.com. Send questions to underthehood@dailyherald.com.