Consumer Guide's® Auto Editors have scoured repair bulletins and questioned mechanics to search for commonly occurring problems for a particular vehicle. In some cases we also give possible manufacturer-suggested solutions. In many instances these trouble spots are Technical Service Bulletins posted by the manufacturer, however, we have our own expert looking at additional vehicle problems.

Check-engine light: The check engine light may come on due to failure of the EGR valve. The Delphi valve is to be replaced with a Seimens valve kit and have the PCM flashed. (2005-06)

Electrical problem: On vehicles equipped with OnStar the global positioning system may lose precision (get off track) and may be caused by window tinting, or, if the antenna is in the rear parcel shelf, by things placed on the shelf. (2005)

Electrical problem: The PCM was being replaced for a defective chip under a voluntary emissions recall because it affected the fuel pump and EGR system. (2005)

Electrical problem: If the OnStar system quits or won't come one (no power), but comes back to life if the fuse is removed for five minutes, the vehicle communications interface module must be replaced or else the problem will recur. (2005-06)

Engine noise: A whistling noise from the 3.5L engine during acceleration is corrected by replacing the PCV tube. (2005)

Engine stalling: The engine may not start or may stall because the tank is empty yet the gauge shows fuel remaining; or the fuel gauge will not show full after refilling due to sulfur corrosion of the fuel level sender. If after treating with Fuel System Cleaner PLUS the problem remains, the sender may need to be replaced. (2005-06)

Engine stalling: The engine may not start, may start then quit, and/or assorted warning lights may glow because the wiring connector under the driver seat may get wet and the contacts corrode. (2005-06)

Horn: The horn may require extra pressure on some spots of the steering wheel pad, and softer springs are available to retrofit. (2005-06)

This table lists costs of likely repairs for comparison with other vehicles. The dollar amount includes the cost of the part(s) and labor (based on $50 per hour) for the typical repair without extras or add-ons. Like the pricing information, replacement costs can vary widely depending on region. Expect charges at a new-car dealership to be slightly higher.

2005 Relay: In a side impact, the outboard release handle on the impact-side 2nd-row bucket seat may be activated, allowing the front and rear seat latches to unlatch. This could increase the risk of injury to occupants. The dealer will remove the seat latch release handle and install a protective cap.

2005 Relay: The parking brake may fail to fully release, causing a noise and the possibility that the parking brake will not keep the vehicle from rolling when next applied, which could result in a crash. The dealer will inspect the rear calipers for parking-brake lever slippage and if necessary, replace the affected calipers.

2006 Relay: Some vehicles were shipped with tire and loading information labels listing an inaccurate vehicle weight capacity. A misprinted label could lead to improper vehicle loading specifications or tire inflation, which could result in tire failure, increasing the risk of a crash. Owners will be provided with corrected labels and installation instructions, or can have the dealer install them.