Skip the auto shop - Our mechanics make house calls

Q: Failed to downshift to lower gear

asked by on

I have 125,000 miles on my car and kept up with all maintenance. Now there is a transmission issue with the computer reading failed to downshift to lower gear. And there is a humming noise after warmup.

A: Greetings. The humming noise is likely caus...

Greetings. The humming noise is likely caused by a faulty PCV valve or oil trap hose. The engine of the vehicle produces a lot of suction and the PCV valve and hose is made to regulate some of the suction by the opening and closing of the valve. The PCV valve commonly becomes stuck open in old age after warming up,which will allow too much air suction. The suction usually can be heard as a humming or whistling noise. The Volvo dealers are aware of the issue and have extended warranties on those parts. I suggest calling your local Volvo dealership and ask them about the warranty of that part on your vehicle. If it is under warranty they will replace it free. Regarding the transmission issue there is a software update available from the dealership that addresses hard shifting and no downshifting. A simple reprogramming will likely fix your problem. If it doesn’t and the transmission still has issues I suggest checking, then changing the fluid if necessary. 80 percent of all transmission failures stem from a fluid related issue.(lack of fluid or old fluid)

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Possible electrical issue in a 2004 Honda Pilot

It appears that you are having multiple and intermittent issues with your Honda Pilot. Following the dealer's recommendations of replacing the gear shifter cable will likely only solve one of your concerns. The issues you describe with your alarm...

Q: Creaking Sound coming from passenger front side when driving

Hello. A creaking sound can be caused by a wide variety of issues. A few common causes are worn suspension components or bushings. The first thing I would do is try to identify where the noise is coming from, and...

Q: Won't Shift into drive, 2008 Pontiac G8

Unfortunately, it sounds like you have an internal transmission problem that will require the transmission be rebuilt or replaced. A transmission that won't go into any forward gear almost always indicates an internal mechanical problem as opposed to an electrical...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...