Why does my engine oil smell like fuel?

Anoopscv · 15th March 2022, 20:02

Hello BHPians, Today I was checking the engine oil level in my Dzire Vxi 2012 model and I could smell petrol in the dipstick

Less than a year ago I changed engine oil and was observing oil stains on the car porch. Recently I did a full service without oil change since I did only 2k kilometers since last oil change.

What could cause this type of smell? Could be due to short drives or something serious to worry?

Jaggu · 17th March 2022, 13:22

How is the oil consistency? has it thinned? Just the smell may not be an ideal way to diagnose. 2012 is a fuel injected engine, so there is no mechanical fuel pump which could have been the case. And I don't think there are any petrol vapor vents into an engine.

Anyways you need to get it checked by a competent mechanic since it can be a case of blown gasket or a piston rings.

Is there any smoke or wet residue at the exhaust tip?

zeng · 17th March 2022, 15:22

Yes, short drives could cause fuel dilution especially during covid19 movement restrictions era.

I suppose the engine oil level is checked and it does not increase higher from before?

Anoopscv · 17th March 2022, 17:03

Quote:

Originally Posted by Jaggu

How is the oil consistency? has it thinned? Just the smell may not be an ideal way to diagnose. 2012 is a fuel injected engine, so there is no mechanical fuel pump which could have been the case. And I don't think there are any petrol vapor vents into an engine.

Anyways you need to get it checked by a competent mechanic since it can be a case of blown gasket or a piston rings.

Is there any smoke or wet residue at the exhaust tip?

Thanks for the reply!. Oil seems to be fine and there is no smoke or wet residue at exhaust. Yes, I will consult with Maruti authorized service center.

Quote:

Originally Posted by zeng

Yes, short drives could cause fuel dilution especially during covid19 movement restrictions era.

I suppose the engine oil level is checked and it does not increase higher from before?

Thanks for your response!. Oil level is normal, seems like I need to consult with the service center.

Jaggu · 18th March 2022, 15:33

Quote:

Originally Posted by Anoopscv

Thanks for the reply!. Oil seems to be fine and there is no smoke or wet residue at exhaust.

I guess it maybe just a false alarm and its just the smell of the oil that has run for some kms. Anyways keep us posted once a mech takes a look at it.

Anoopscv · 18th March 2022, 16:07

Quote:

Originally Posted by Jaggu

I guess it maybe just a false alarm and its just the smell of the oil that has run for some kms. Anyways keep us posted once a mech takes a look at it.

Today I visited the Maruti service center and after some checks they confirmed everything is fine. But for my satisfaction I asked them to smell the oil in another vehicle(new model Dzire) and I found it smells the same. Looks like its normal but the Mobil 1 FS X2 5W-40 which is left out in the oil bottle has an 'oily' odour.

Kosfactor · 18th March 2022, 16:28

@Anoopscv - Some fuel makes it way into the oil but if you drive the vehicle long enough at operating temperature, the fuel flashes off due to heat, makes it way into the intake through PCV system and gets burned off!

One more reason to plan a road trip

SS80 · 18th March 2022, 16:48

It's always best to change the engine oil every one year or 7k km(whichever comes first). Also, try to check if there are any rubber hoses cracked due to ageing or summer. Sometimes fuel hoses do crack and cause this type of smell.

CretaKumar · 29th November 2022, 11:09

Quote:

Originally Posted by Kosfactor

@Anoopscv - Some fuel makes it way into the oil but if you drive the vehicle long enough at operating temperature, the fuel flashes off due to heat, makes it way into the intake through PCV system and gets burned off!

One more reason to plan a road trip

Practically this doesn't happen. When diesel or petrol mixes with Lubricant. They form a homogeneous mixture hence bringing down the overall evaporation temperature of Oil. Tbh this takes a major toll on engine.
However PCV valve has a different function, its short for positive crankcase ventilation which just ensures that crankase is ventilated and pressure due to blowby gasses and oil vapours doesn't harm the engine.

About oil smelling like petrol, its pretty much normal. But ensure that oil level doesn't increase. Thats the only indicator to look at.

15th March 2022, 20:02	#1
Anoopscv BHPian Join Date: Mar 2014 Location: Bangalore Posts: 68 Thanked: 34 Times	Why does my engine oil smell like fuel? Hello BHPians, Today I was checking the engine oil level in my Dzire Vxi 2012 model and I could smell petrol in the dipstick Less than a year ago I changed engine oil and was observing oil stains on the car porch. Recently I did a full service without oil change since I did only 2k kilometers since last oil change. What could cause this type of smell? Could be due to short drives or something serious to worry?
	() Thanks

17th March 2022, 13:22	#2
Jaggu Team-BHP Support Join Date: May 2004 Location: Bangalore Posts: 20,381 Thanked: 17,282 Times	Re: Why does my engine oil smell like fuel? How is the oil consistency? has it thinned? Just the smell may not be an ideal way to diagnose. 2012 is a fuel injected engine, so there is no mechanical fuel pump which could have been the case. And I don't think there are any petrol vapor vents into an engine. Anyways you need to get it checked by a competent mechanic since it can be a case of blown gasket or a piston rings. Is there any smoke or wet residue at the exhaust tip?
	(1) Thanks

17th March 2022, 15:22	#3
zeng BHPian Join Date: Aug 2021 Location: Kuala Lumpur Posts: 180 Thanked: 107 Times	Re: Why does my engine oil smell like fuel? Yes, short drives could cause fuel dilution especially during covid19 movement restrictions era. I suppose the engine oil level is checked and it does not increase higher from before?
	(1) Thanks

18th March 2022, 16:28	#7
Kosfactor Distinguished - BHPian Join Date: Oct 2018 Location: COK\BLR\MYS Posts: 3,855 Thanked: 11,203 Times	Re: Why does my engine oil smell like fuel? @Anoopscv - Some fuel makes it way into the oil but if you drive the vehicle long enough at operating temperature, the fuel flashes off due to heat, makes it way into the intake through PCV system and gets burned off! One more reason to plan a road trip
	(1) Thanks

18th March 2022, 16:48	#8
SS80 BHPian Join Date: Apr 2019 Location: Bangalore Posts: 264 Thanked: 991 Times	Re: Why does my engine oil smell like fuel? It's always best to change the engine oil every one year or 7k km(whichever comes first). Also, try to check if there are any rubber hoses cracked due to ageing or summer. Sometimes fuel hoses do crack and cause this type of smell.
	(1) Thanks