Honda Civic 1.6 - Humming noise, power drop

[voocash1]

I have this Honda Civic 1.6i VTEC Petrol about 105k milage. I will go straight to the point:

On my normal commute to work all of sudden a humming noise comes out of engine/gearbox. I can feel small vibrations on the steering wheel also the power drops significantly - it almost doesn't accelerate at all. In last few weeks I have noticed a MPG drop as well from 41 to 38.5 and it still dropping.

When the problem occurs I can feel like the engine is under higher load, like it was put on dyno test. It really struggles to accelerate if so. I recently changed oil and oil filter. But it didn't solve the problem. Summing up:

• Humming noise from a gearbox/engine at 60mph after 10mins of drive, goes away when slowed down to 40mph
• Small vibrations felt on the steering when it happens
• MPG drop in last few weeks and is still dropping

• It's NOT misfiring
• Oil is NOT leaking from the gasket or engine
• Replaced oil filter recently - no difference
• Garage said they can't see anything special
• I have no records of servicing or repairs on this car - I own it for 2moths

I Googled a bit and potential clues may be:

• Clogged fuel filter
• Bearing on a gearbox shaft ?
• Fault spark plugs?

Have you come across such issue ?

Edited by voocash1 on Monday 18th February 21:58

Edited by voocash1 on Monday 18th February 21:59

[GreenV8S]

voocash1 said:

It's NOT misfiring

How do you know?

A misfire would cause vibration and loss of power.

[voocash1]

GreenV8S said:

How do you know?

A misfire would cause vibration and loss of power.

I had misfiring in my previous car. This is different. Engine doesn't judder, I don't hear any blowing noises. Engine works fine and smooth apart from the fact it is louder and I can definitely sense the resistance of being put under higher load.

Edited by voocash1 on Tuesday 19th February 09:00

[E-bmw]

voocash1 said:

GreenV8S said:

How do you know?

A misfire would cause vibration and loss of power.

I had misfiring in my previous car. This is different. Engine doesn't judder, I don't hear any blowing noises. Engine works fine and smooth apart from the fact it is louder and I can definitely sense the resistance of being put under higher load.

Edited by voocash1 on Tuesday 19th February 09:00

Just because you can't hear a blowing noise doesn't mean you don't have a misfire.

A misfire can be quite subtle & yet lose a lot of power.

Have you had it connected to anyone with a proper code reader?

Have you had your plugs off?

I would be looking at plugs/leads/coil/coils if it were my car as you are perfectly describing a misfire.

[voocash1]

Other clues are pointing at seized calipers.
I will also go to garage to plug it in for any misfire issue.

[GreenV8S]

voocash1 said:

I can definitely sense the resistance of being put under higher load.

A loss of power can lead to the perception that there is resistance somewhere, but the amount of power involved is not easy to absorb and if it really was that (rather than a simple loss of power) then things would be smoking hot and catching on fire within minutes.

The symptoms you're describing match a loss of power caused by a misfire. A misfire can feel different on different cars, but vibration and loss of power ticks all the boxes.

[GreenV8S]

voocash1 said:

Other clues are pointing at seized calipers.
I will also go to garage to plug it in for any misfire issue.

Touch each wheel after a ten minute drive where the symptoms occur. If you didn't burn your hand, you probably don't have binding brakes.

[voocash1]

I'm coming with some answers lads.

Thanks for all helpful clues and advice. It was the caliper, indeed. Left Front caliper was seized and it was causing a resistance and friction. Left alloy was quite warm after 10min drive without excessive use of brakes. I have replaced it together with new brake pads and all is coming back to normal. MPG is increasing after first 20mil driven so it is surely a good sign.

After repair my right wheel is getting warmer than normal now... I guess when they replaced brake pads they didn't assembly it rightly! What a poor a garage! At least I know what is going on now.

Thanks again for prompt help!

PS. Poor mechanic couldn't spot it after I visited him twice. I think I have to change garage ...

[GreenV8S]

Glad to hear that you've found the problem. It's easy to be lazy when you're replacing pads and not bother cleaning and greasing the hardware. It might not cause problems right away, and if you're against the clock or eager to get off home I guess some people will be tempted to cut corners.