Can't Find the Squeal
Q:I have a 2WD 1995 Ford Ranger regular-cab, longbed pickup with a 2.3-liter four-cylinder engine and five-speed manual transmission. Under part throttle in third gear between 25 and 30 mph, and again in fourth between 35 and 40 mph, it makes a squealing/whistling sound that seems to come from the engine. I was able to duplicate this noise for a technician, who thought it could be coming from the exhaust system. The following parts have already been replaced: timing belt, water pump, fan clutch, alternator, and the serpentine belt and its idler and tensioner pulleys. The noise sounds like a dry bearing squeal that only occurs under light load, part throttle at certain rpm.
A:Tracking down mystery noises can be a tough job. You've already eliminated a group of suspect parts and therefore narrowed down the list of potential causes. If the technicians working on your truck have yet to incorporate modern technology into the diagnostic process, now's the time. A Ford service department should have several tools that are invaluable in locating hard-to-find noises and vibrations. One is the ChassisEAR, an electronic listening device specializing in the detection of chassis-related noises while road-testing the vehicle. The EngineEAR can detect even the faintest noises from the engine and other attached parts such as the air-conditioning compressor or power-steering pump. There's also a handheld Ultrasonic Leak Detector that can pick up wind noise, vacuum leaks, and more. Ford service information has a detailed step-by-step procedure for categorizing and troubleshooting this type of condition. You should focus on an atypical leak or obstruction in the exhaust system, possibly in the catalytic converter. Also pay careful attention to any vacuum leaks or restrictions at the engine, leaning toward the PCV valve and hose, which are large and vulnerable sources of vacuum.
Careful Steering-Wheel Removal
Q:I need to replace my 2002 Dodge Ram 1500's steering wheel, and the current wheel doesn't have the remote control for the radio switches. My questions: First, how difficult is it to replace the actual steering wheel with respect to the airbag? Second, are the remote radio controls already wired and just need to be connected or would there be more to it than that?
A:First, and most important, the airbag system must be fully disabled by disconnecting the battery and allowing two minutes for the system to discharge. This will prevent accidental deployment and serious injury. That said, the wiring harness for the airbag and remote radio controls is connected through a "clock spring" located behind the steering wheel on the steering column. The clock spring is a wound-up group of wires that allows the steering wheel to rotate back and forth without breaking the wires. If your Dodge Ram didn't come from the factory with the remote radio option, the appropriate wiring wasn't installed and adding a steering wheel equipped with radio control switches isn't going to make it work. Replacing the steering wheel involves the removal of the airbag mounting screws, disconnecting its electrical connector, and loosening the steering-wheel retaining bolt before installing a special steering-wheel puller tool. Be sure to have the wheels straight ahead and the steering wheel centered before removal. Then mark and reinstall the steering wheel in exactly the same spot. This will keep the clock spring centered and prevent a future break in the airbag wiring.