Letters: Ignition switch could cause car to shut off

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Q: I’m having an issue with my 1995 Oldsmobile 88. After driving it for about 20 miles it will completely shut off. I can start it right up without any problems. This will occur around three times during my drive. What could be wrong? Please help. — Betty, email

A: There are several possibilities. But one of the first things to check would be the ignition switch. Especially since the car starts back up without any trouble. The ignition switch could be worn out and the contacts could be separating due to vibrations.

You may want to try jiggling the ignition key a little while the engine is running. See if you can get the engine to shut off while jiggling the key. If jiggling the key causes the engine to shut off, have the ignition switch replaced.

Other possible causes include the crankshaft position sensor or ignition module. But usually when these components begin to fail, they’ll cause the engine to stall and typically will not let the engine start back up until after the engine has cooled down a bit.

A technician may need to drive your car for a period of time while monitoring some inputs (like the crankshaft position sensor) to the powertrain control module. Diagnosis will be challenging if the problem does not occur for the technician during the road test.

Q: I’m thinking about buying a used (good condition) 2006 Toyota Tacoma with 116,000 miles. It has the V-6 engine, and I’m wondering if it will need a new timing belt soon. — Jack

A: The 4.0-liter V-6 engine in that ’06 Toyota Tacoma uses a timing chain, not a belt. A timing chain is more durable than a belt and there is no recommended replacement interval for it. It is generally replaced only when it becomes noisy, excessively worn or breaks.

Q: I’m trying to save money on my auto insurance. When is the best time to drop the collision insurance? My car is a 1998 Toyota Camry with 56,000 miles. — Jerry, Oak Lawn

A: There are a number of things to consider before deciding to downgrade your car insurance. First, you need to know how much your car is worth. You can do this by visiting various websites like Kelley Blue Book (kbb.com) or Edmunds (edmunds.com).

If the current value of your vehicle is considerably low, you should definitely consider dropping collision and comprehensive insurance. Your financial situation also should be taken into account before downgrading your insurance. You need to know if you could afford to repair or replace your car yourself if you didn’t have collision and comprehensive insurance and you were the cause of the loss.

Obviously, you also need to consider how much you are currently paying annually for that additional collision and comprehensive insurance, and what your deductible is.

Here’s a hypothetical situation: Let’s say your car is worth $4,000 and you have a $500 deductible. The most money you would get from your insurer if you suffered a total loss would be $3,500. Generally, if the cost of carrying the additional collision and comprehensive insurance is more than 10 percent ($350 in this hypothetical case) of what you would receive from a total loss, then you should definitely think about downgrading.

Questions for Ira Siegel? Call the Auto Advisor Hotline at (708) 633-6839 or e-mail ira.siegel.is@gmail.com. Siegel is an automotive instructor and an automotive service excellence-certified master auto technician.