Why does the oil light come on sometimes?
Q. My 2005 Ford Explorer has a problem where the temperature gauge spikes after driving for 20 miles or so. At the same time, the oil light comes on. If I shut the car off and wait 30 minutes, it is fine again for a while. What do you think is wrong?
A. The first thing to determine is if the problem is with the engine or if it is a combination of false reading from the gauges. Have a good repair shop hook up gauges and test the engine temperature and oil pressure reading. If these readings are low, then further diagnostic work will need to be performed. The problem could be that the engine is, in fact, overheating, causing both the oil and temperature lights to come on. Continuing to drive with these problems will guarantee more expensive repairs. If the readings are normal, then the technician will need to check the gauges, wiring and sensors/sending units on the engine to determine the problem.
Q. I took my 2001 Chevy truck to a garage for a state inspection the other day and they said the whole car was fine except that there was a lot of “play’’ in the rear axle. They put my truck on a lift and one of the mechanics simply grabbed my rear driver side tire and started pulling back and forth and it was able to slide in and out maybe 2-3 inches. It seemed like significant movement. The mechanics said there was no way to tell what was causing this issue without pulling it apart and they wouldn’t even give me a ballpark price quote. I put the car on jack-stands at my house when I got back from the shop and was not able to replicate the movement of the rear axle. Both rear tires were in the air, I spun them into different positions, put the truck in park, neutral, reverse and drive and I couldn’t get the axle to move in and out like they showed me at the shop. I’m wondering why I was not able to replicate the movement but I do notice a clicking sound, what could be the cause?
A. The rear axle is held in place with a “C’’ clip inside of the rear differential. Some movement is possible but several inches of movement definitely requires some further investigation. The clicking noise could be related to one of the bearings of the differential beginning to fail. I would start with removing the rear axle cover to see exactly what is going on inside of the differential. Although there will be costs associated with just doing the inspection it should be minimal. This inspection is definitely is necessary to find the cause of the problem and create an estimate of repair costs.
Q. I recently read a story about how diesels are a better value than gas cars and based on that story I have been thinking about buying a new car with a diesel engine. Are diesels really a better value? My other concern is how hard it will be to start in the winter?
A. Years ago in cold weather, it was not usual to have to plug in a diesel vehicle to allow for easy starting. This is not generally the case today. I have driven several late model diesel vehicles in cold weather and none of them needed any additional help to start. This has included the diesel Grand Cherokee, Audi A6 and Volkswagen Golf. My only word of caution is that it is very important that in cold weather, the diesel fuel is rated for winter use. I spoke with several owners of diesel vehicles last year that had a problem with their cars but the problem was related to the fuel in the tank, not the car itself. If you buy a diesel, buy fuel from a high volume gas station. Regarding the overall value of a diesel if you look at fuel savings it is hard to make an argument for a diesel. The fuel costs more and to recoup the extra cost of the diesel engine can take quite a while. As an example let’s look at the VW Jetta and Chevy Cruze. The base Jetta with the gas engine costs $20,915 and the Jetta diesel costs $23,500. The diesel car is $2645 dollars more expensive and it would take 13 years to see the savings in fuel costs. Looking at the Cruze base Cruze ECO is $22,195 and the diesel Cruze is $26,485. The diesel has a $4290 premium it would take 85 years to pay off the difference in price based solely on fuel economy.(These number come for the website www.fueleconomy.gov) The saving for a diesel can come from depreciation and lower maintenance costs. Taking a look at a 2012 gas Jetta, the trade in value is $11,175 and the diesel Jetta has a trade in value of $16,575. So if you look at depreciation, the $2650 premium that you pay to buy the Jetta Diesel turns into a $5400 savings in three years. You need to look at all of these factors and your driving habits to see if a diesel car makes sense for you.
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