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Link to listen to the engine

The car is a skoda fabia mk 2 from 2014. Recently after a road trip the engine oil light went yellow, but looking at the dipstick it appeared that there was enough oil in the car.

The oil didn't appear a funny colour, and I made sure to test it on flat ground, after cooling down and after warming the engine. Regardless the light persisted (switching off after opening the bonnet, and returning after ~100km as described in the manual).

So I added a bit more oil, and ever since the engine has sounded a bit more aggressive and 'poppy' if that makes sense? I've been told that happens when you add oil, but this sounds more aggressive than I'd expect. The warning light is gone, but the noise worries me.

Thanks for any help I can get.

Here are the specs:

Year: 2014

Make: Skoda

Model: Fabia

Engine Size: 1.2L

Transmission Type: Manual

Milage: ~110k

John Waiton
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2 Answers2

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If you have added oil to your engine to bring the oil mark on the dipstick higher than the "FULL" line, you should remove the excess as soon as possible. If an engine contains much more oil than the "FULL" mark, moving engine parts can whip the oil into a foam.

Foamed oil does not pump like liquid oil, and the result can be engine damage from lack of oil pressure, giving poor lubrication. That's right. Adding much more oil than required can give you low oil pressure which can destroy your engine.

The oil light on your instrument cluster does not warn of low oil unless the engine has lost almost all of its oil. Instead, it warns of low oil pressure.

If your oil pressure light comes on, either you have low oil pressure for some reason or you have good oil pressure but a defective oil pressure sensor or sensor wiring. (The sensor is also called a "sender".)

To diagnose the problem, if you wish to do it yourself, you need an oil pressure gauge and a means to attach it to your engine. A gauge with fitting and a hose is available as an "oil pressure test kit" available at auto parts stores or online. A port to attach the kit to the engine is usually located near the oil filter.

If you find that you actually have good oil pressure but the light comes on, then the repair is to check the wiring to the oil pressure sensor, and if it is good, replace the sensor. They are inexpensive.

If you really do have low oil pressure according to the test gauge, you must further diagnose the cause. Low oil pressure could be caused by a defective oil pump, from using the wrong oil in the engine, from dilution of the oil with fuel, or from worn internal engine parts caused by poor maintenance.

If an oil pressure test shows that you really do have low oil pressure, you can start a new question here for further advice.

MTA
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Based on your recording, it sounds like you have developed an exhaust leak. Check the exhaust manifold for cracks, a worn exhaust gasket, the EGR valve (if equipped) and related exhaust tubing. Be sure to also check for head gasket leak -- through a compression check and leak down tests - before spending any money.

I did hear a bit of low speed ping, which points to the possibility of foamed oil that MTA describes. This can cause your engine to sound more aggressive, as certain components may not be lubricated properly.

An overfilled crankcase increases the crankcase air pressure. Oil may have forced its way into the PCV valve (if equipped), causing it to clog, which will certainly cause the engine to run rough. Replace the PCV valve if in doubt.

Another possibility is excessive oil dislodged carbon within piston ring groves by overwhelming the oil control rings, causing poor combustion and excessive blow-by gases due to sticky piston rings. In this case, a crankcase flush and oil change is in order, perhaps even twice in a short duration of a week.

Carguy
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