My '06 Malibu does not start. When I turn the key, the engine clicks -- nothing else. If I hold the key in the start position, it clicks once every second or so. The engine and security lights show as normal when the key is at start, as well as the oil and battery lights. The security light never flashes. The battery connections are clean, and my multimeter reads 12.22 volts with the key off. A scan tool pulled up a P1682 fault code. A Chevrolet dealer told me the problem is either a bad passlock sensor or body control module (BCM).
A Before you do anything else, either fully charge your battery, try a booster battery or try a different battery. Open-circuit voltage of 12.22 indicates a battery that's nearly dead and likely won't crank the engine. You need at least 12.5 volts for a battery to crank an engine.
The P1682 fault code can indicate a connection or communication problem with one of the many control modules in your vehicle. My Alldata database pulled up service bulletin 09-06-03-004D, dated December 2010, that identifies potential "no crank/no start" issues caused by "fretting" corrosion on one or more electrical connectors. In this case, locate and identify the body control module on the passenger side of the center console. Disconnect the battery, then unplug and inspect the multiterminal electrical connector on the BCM. Fretting corrosion appears as dark smudges at the point of contact between pins in the connector. Cleaning and reapplying dielectric grease can restore the connection.
Q Last February, I purchased a used 2010 Chevy Tahoe with 15,000 miles on it from a Chevrolet dealer. I've noticed that it idles rough and it feels like the engine is "missing." When I leave it idling, it shakes and feels like the engine might die. When I start off from a stop, it immediately has a "dead spot" and hesitates before it accelerates. After I shut the vehicle off, I notice a bad smell, almost like a sewer-type smell.
The dealer couldn't find any fault codes and didn't find any software updates. The service tech told me that it's normal and there's nothing that can be done about it. He said they checked the gas and said that there was too much ethanol in it -- 16 percent. I'd appreciate if you could check the Alldata database to see if there are any service bulletins for my vehicle.
A Have the dealer check the oxygen sensor signals with a scan tool to see if the computer is trying to adjust the fuel/air mixture to correct for a too-lean or too-rich condition. Also, have the dealer perform an emissions test to determine whether exhaust emissions are within legal limits. Your vehicle is still covered by the original GM powertrain warranty as well as the federal eight-year, 80,000-mile emissions warranty.
The "it's normal" comment is unfounded. From your description, the engine is running either too lean or too rich, causing misfires, rough running and excess unburned hydrocarbons in the exhaust. The higher percentage of alcohol in the fuel could be a contributing factor.
Q My daughter has a 2000 Chevy Impala with the 3.8-liter V6 engine. The "traction active" light intermittently comes on, and the engine is sluggish when she puts it in gear. The garage says this is a common problem and has to do with the wearing of the tires. They have rotated the tires to no avail. They think the next step is to replace the tires that have about 30,000 miles on them.
A Has the shop scanned for fault codes? It is possible that low tire pressure or a malfunctioning tire pressure monitor could trigger a warning light with the antilock brake system or traction control. But unless extraordinary tire wear has created a significant difference in tire rolling diameters, worn tires aren't the problem.