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Motor Noise after Maintenance

I have a 2008 Honda Fit, automatic with about 71K miles. At my last oil change on December 9, 2012, I also had the transmission fluid changed. Ever since then, there has been a low grade noise under the hood that is not my usual quiet, purring motor! In trying to isolate when the noise occurs, I’ve noted that it can be irritatingly heard when the car idles in both Drive and Neutral. (Initially, it was only when the car was in Drive.)…and when I’m driving the car anywhere up to about 30mph. Any ideas about what is causing this, would be welcome…and if it is the result of maintenance performed. Thank you.

Did you have this work done at a reputable mechanic or a quick-lube place? Are the oil and transmission fluids at the right level now? Was Honda transmission fluid used (which is strongly recommended in a Honda)?

In addition to checking the items that lion9car recommended, I strongly suggest that the OP check the air intake ducting to see if it might have been disconnected/ not properly re-connected during servicing–especially if the air filter was changed or checked. It is very possible that the OP is hearing the unmuffled noise of air being drawn into the engine through a disconnected air intake.

I too wondered if the work was done at a quickie lube. If it was, they might have used the incorrect tranny fluid. Their business model encourages the use of one common fluid, and some makes are very specific about their tranny fluids.

Wherever the work was done, I’d suggest checking your fluid levels per your owner’s manual before driving the vehicle again. If the levels are good, have the work double checked by a reputable shop, and of the fluid was changed at a quickie lube, tell the shop that this is a concern and let them fluid the system with the proper fluid.

Like everyone is saying, Honda factory fluid is very important to keep your trans working properly. Also, the proper way to check fluid level on Honda automatic transmissions, unlike most other car brands, is with the engine OFF, not running, and it being at operating temp. So a lot of shops check it running, think it’s low, and add 2-3 quarts, and it’s 2-3 quarts overfilled.

Great people, great advice on this site. Thanks! I’m the owner of the 2008 Honda Fit with the motor noise complaint. I drove the car back to the Firestone shop where I’ve had work done on my cars for years. Fluid levels checked out fine and were done after engine operation, but not running. Also, the invoice states that Honda transmission ATF fluid was used during the drain and flush. When I mentioned the air intake duct, one of the mechanics said an engine light would be indicated if it was loose. While the manager is a great guy, he did admit not knowing much about Honda Fit cars…so advised taking it to a Honda dealer. Guess that will be my next step. Again, many thanks!

A loose induction system piece will not necessarily trip a Check Engine Light unless it’s in a place and large enough to affect airflow past the Mass AirFlow sensor. Your induction system is comprised of plastic and rubber flow passages that you can check yourself without any danger of hurting anything. There will probably even be an appendage in the pathway that’s there to mitigate pulses in the airstream, creating a smoother and/or quieter flow. I modified my induction system to a ram air system of my own design, and the sound now resembles a motorcycle somewhat when I accelerate. It sometimes takes little to change the sound of the engine.