Service slants

Motor, Oct 1999 by Juran, Ken

Note: DTCs cannot be erased if the stop light switch is not turned on and off in the proper sequence or if the alternator L terminal voltage increases to a high-voltage state, says Chrysler.

Toyota

Replacing front axle hub nuts. You're probably aware that the front axle hub nut on 1992-98 Tercels, Paseos, Corollas, Celicas and Camrys, and 1996-98 RAV4s, are not reusable. However, you may not be aware that there are two different nuts in use on these vehiclesone silver, the other black. What's important is that whenever you install a new nut, it must be the same color as the old one. The silver (Part No. 9017922020) and black (Part No. 9017822001) nuts are not interchangeable.

Porsche

Oxygen sensor trouble. Porsche reports that the 02 sensors on 1995 and newer 911 Carrera and 911 Turbo models (993 chassis) can act up if the connectors in the engine compartment are cleaned or treated with contact cleaners or other sprays, oil, grease, water, etc. Typically, the 0, sensor(s) will go belly up, or there may be a false DTC set in the PCM, accompanied by an illuminated MIL. The reason for this, according to Porsche, is contamination of the sensor's needed reference air, which is pulled through the cable harness and the electrical connector. Therefore, anytime you reconnect one of these sensor connectors, make sure it's clean and dry.

Next, before testing a suspect oxygen sensor, disconnect it and drive the car to operating temperature at 3500 to 4000 rpm for about 10 minutes. Porsche says this should burn off any sensor contamination, and yield better test results.

Possible DTCs you might come across include P0130 (02 sensor ahead of catalyst) through P0160 (02 sensor behind catalyst) on OBD 11 1996 911 Carrera and 911 Turbo, and Signal Unplausible or Open Circuit on OBD I cars prior to 1996.

Saab

Binding throttle lever recall. Saab recalled its 1994-97 900 models around May 1997 to replace the zinc-coated throttle control lever bushing with a nickel-coated bushing and bolt because corrosion around the zinc-coated bushing was causing binding throttle levers-not a good thing when you want to stop. If you ever come across one of these vehicles that didn't get its throttle lever bushing updated, refer the customer to a dealer for the free fix. You'll not only be doing him a favor, you may also be saving his life!

Saab also notes that "owners who take their vehicles to an authorized dealer on an agreed-upon service date and do not receive the free remedy within a reasonable th-ne should contact Saab at 800-9559007. Also contact the National Highway Traffic Safety Administration's Auto Safety Hotline at 800-424-9393." IM