‘Car Doctor’ Q&A – Saratogian
Q. I have a 2005 Mercedes Benz E500 station wagon. The car has over 200,000.00 miles on it and lately when I’m stationary the car acts like it’s out of gas and then it will go forward. When I feel it happening, I try to leave plenty of room with the car in front of me or at a red light. Other than this issue, the car runs great, the oil has been changed regularly and recently the harmonic balancer was changed (a mechanic told me this would fix the problem). I want to keep the car because in the snow the car with the 4-Matic all-wheel-drive system is a tank that plows the snow.
A. From your description, it sounds more like the engine is running very lean intermittently. When this happens, the engine compensates and increases engine speed. This could be due to a vacuum leak or a leak in the air intake system. The other possibility is the throttle control/actuator or actuator wiring.
Q. I have an older Chevy and the heater fan only runs on high. The switch seems ok, what’s wrong?
A. There is a heater fan resistor which over time will fail and the fan will default to the high speed fan setting. Replacing the resistor in most Chevrolet vehicles is a relatively simple repair.
Q. I have a 1994 Infiniti J30. I have kept it in good condition for many years as a casual car. Last year the power door locks started to partially lock and unlock when I pressed the inside button or key fob. Now I can’t open the doors to get in, either by fob or even by key! and access to interior knobs or handles does not open the doors. Now the battery is dead and I can’t do anything. I’m thinking of pulling the lock on the door or breaking the window in desperation. Ideas?
A. I am issuing a faulty door lock actuator. The first thing you’re going to have to do is open the hood to charge the battery. Maybe try the trunk, some vehicles allow you to access the cabin through the trunk. As for opening the door with the windows down, try pressing the door release button while trying the door knob and handles. Sometimes you can get lucky and the lock will open. Before you damage the car, call a good automotive locksmith, they may be able to open one of the doors (maybe a back door) without any damage.
Q. Recently my door handles stopped giving me the door lock confirmation beep when I press the lock button on the key fob. The tailgate also stopped beeping when it opens and closes. This is a 2014 Acura MDX. I was told the smart buzzer module in the rear bumper controls this, and a replacement will fix this. I’m just trying to confirm this before buying the coin at $70.00.
A. The smart horn module is located behind the rear bumper and unfortunately the diagnostic procedure ends with the statement “Replace with a known good part”. Even using an Acura-specific scan tool cannot completely confirm the faulty part.
Q. I have always changed my vehicle’s brake fluid regularly based on time, not mileage. I saw you note that the brake fluid should be changed at 30,000 miles. The car manufacturer recommendations I saw were also based on mileage. Since brake fluid needs to be changed because it absorbs moisture, does it matter whether the car is driven or just sat?
A. The rules for replacing brake fluid are as varied as the manufacturers. As an example, Honda recommends fluid replacement every three years, Subaru every 36,000 miles, some GM vehicles every 45,000 miles, and some have no recommendations other than inspecting the fluid when servicing. routine maintenance. The absolute best method for testing brake fluid is to measure for moisture contamination. Moisture can cause rust, and rust can lead to very expensive repairs to brake systems.
Q. My Kia Niro shows 90,000 miles. I have no problem but does the transmission fluid need to be changed? I just don’t see how to do the job. There is no gauge and is there a filter?
A. Kia doesn’t have a spec (or at least one I can find) for changing the fluid in this transmission. The Niro’s transmission is a dual-clutch automatic, so unlike a conventional automatic transmission, there’s no actual filter. Other manufacturers use a DSG type transmission with recommended fluid changes every 30-50,000 miles. I’ve seen some Kia dealerships report that the fluid should be changed every 30,000 miles. The service consists of draining the old fluid and filling the transmission with fresh fluid.
Q. I have a 2018 Honda CR-V that has a distinct clicking noise that emanates from under the driver’s side dash when I get into the car to start it. It doesn’t always click, but many times it does. This sometimes seems to prevent the car from starting or the battery does not seem to be fully charged. We are not using the vehicle as we did before Covid started. I replaced the battery in January because the one that was there died. I’ve noticed recently that when I turn the steering wheel to the far left or right, the power steering seems to momentarily shut off. It’s been going on for a year and a half. It’s intermittent so I haven’t had a clear solution offered to me. Thoughts?
A. I suspect the rattling noise has more to do with not driving the vehicle as often. I think the noise is caused by the Electric Brake Booster (EBB) system. The system will turn on for approximately 3 minutes each time a front door is opened. There was a technical bulletin that stated that the noises were just normal vehicle operation and did not indicate a vehicle problem. Regarding the steering, there may be a recall that affects this vehicle. I would call the Honda dealership or check the NHTSA website for a recall on your vehicle.
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