Car Doctor Q&A

Q

I have a 2005 E500 Mercedes Benz wagon. The car has over 200,000.00 miles on it and lately when I am at a standstill the car acts like it is running out of gas then it will lurch forward. When I feel this coming on, I try to leave a lot of room with the car in front of me or at a red light.me. Other than this issue the car runs great, oil changed regularly and recently the harmonic balancer was changed (a mechanic told me this would fix the issue). 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 through the snow.

A

From you description it sounds more as if the engine is intermittently running very lean. When this happens, the engine will compensate and raise the engine speed. This could be due to a vacuum leak or leak in the air intake system. The other possibility is the throttle control/actuator or wiring to the actuator.

Q

I have an older Chevy and the heater fan only works on high. The switch seems ok, what is wrong?

A

There is a heater fan resistor, that over time will fail and the fan will default to the high-speed fan setting. Replacing the resistor in most Chevrolet vehicles is relatively simple repair.

Q

I have a 1994 Infiniti J30. I’ve kept it in good shape for many years as an occasional car. Last year the power door locks began locking and unlocking partially when I pushed the inside button or fob. Now I can’t open the doors to get in, no matter if by fob or even key! and accessing the inside buttons or handles don’t open the doors. Now the battery is dead, and I can’t do anything. I am thinking of having the door lock pulled or break the window out of desperation. Any ideas?

A

I issue is a faulty door lock actuator. The first thing you are going to need to do is get the hood open to charge the battery. Perhaps try the trunk, some vehicles you can access the passenger compartment through the trunk. As for getting the door open with the windows down try pushing the door unlock button while trying the door button and handles. Sometimes you can get lucky, and the lock will open. Before you resort to damaging the car, call a good automotive locksmith they may be able to get one of the doors open (perhaps a rear door) without any damage.

Q

Recently my door handles stopped giving me the door lock confirmation chirp when I press the lock button on the fob. The tailgate has also stopped making the chirp warning sound when it opens and closes. This is a 2014 Acura MDX. I was told that the smart buzzer module located in the rear bumper controls this, and a replacement will fix this problem. I’m just trying to confirm this before purchasing the $70.00 part.

A

The smart buzzer module is located behind the rear bumper and unfortunately the diagnostic procedure ends with the statement, “substitute with a known good part”. Even using a Acura specific scan tool can’t completely confirm the failed part.

Q

I have always regularly changed my vehicle’s brake fluid based on time not mileage. I have seen you note that brake fluid should be changed at 30,000 miles. The auto manufacturer recommendations I have seen have been mileage based as well. Since brake fluid needs to be changed since it absorbs moisture, does it matter if the car is driven or just sitting?

A

The rules for brake fluid replacement are as varied as

the manufacturers. As an example, Honda recommends fluid replacement every three years, Subaru every 36,000miles, some GM vehicles every 45,000 miles and some have no recommendation other than inspect the fluid during routine service. The absolute best method for testing brake fluid is to measure for moisture contamination. Moisture can cause rust and rust can cause very expensive repairs to brake systems.

Q

My Kia Niro has 90,000 miles on it. I’m not having any problems but does the transmission fluid need to be changed? I just don’t see how to go about doing the job. There is no dipstick and does it have a filter?

A

Kia doesn’t have a specification (or at least one I can find) to change the fluid in this transmission. The transmission in the Niro is a dual-clutch automatic, so unlike a conventional automatic transmission there is no actual filter. Other manufacturers the use DSG type transmission with recommend fluid changes every 3050,000 miles. I have seen some Kia dealers post the fluid should be changed every 30,000miles. The service is a matter of draining the old fluid and refilling 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 side dashboard when I enter the car to start it. It doesn’t always click, but many times it does. This sometimes seems to cause the car not to start or battery seems not up to a full charge. We don’t use the vehicle like we used to before Covid started. I replaced the battery back in January because the one that was there died. I have noticed lately when I turn the steering wheel to the extreme left or right the power steering seems to momentarily cut out. This has been going on for the last year and a half. It is intermittent so I have not had a clear solution offered to me. Any thoughts?

A

I suspect the clicking noise has more to do with not driving the vehicle as often. I believe the noise is caused by the electric brake booster (EBB) system. The system will come on for about 3 minutes most every time a front door is opened. There was a technical bulletin that stated the noises are just normal vehicle operation and don’t indicate a vehicle problem. Regarding the steering there may be a recall that effects this vehicle. I would call the Honda dealer or check with the NHTSA website for recall on your vehicle.