Car serviced and now mpg is lower?!

3t3p · 02-03-2023, 03:30 AM

Had my car serviced, really only an oil change and they ran injector cleaner through.
First tank of petrol didn't notice much but then thought the car seemed very happy and I'm waiting for my plugs and engine air filter to arrive.

Only other variable is it's become warmer.

My km per litre has dropped from 10 or so in town to 8-8.5?!

The right foot is about the same.

Am I going nuts?!

Moloc · 02-03-2023, 01:40 PM

I'm running in the 8's with spirited driving around town. Got it down to 7.8 once.

agent_orange · 02-03-2023, 05:17 PM

First oil change in NZ after moving from the UK?
What oil did they use?
BMW Australia uses TwinPower M 0W40 LL-01 for the turbo M cars, not the thinner stuff used in north America.
May be the same with NZ vs UK? Wouldn't make as much of a different to fuel economy as what you are seeing I would have thought though.

///M TOWN · 02-04-2023, 01:46 AM

OP…. What transmission do you have… ⁉️

3t3p · 02-08-2023, 03:58 AM

Manual.

She did have an oil change on arrival to the country.

5W-30 I'm sure is what he said was put in.

Only other change is going 255/35 to 275/35. But when those were brand new I actually had 11kml/l. Then it stabilised to 10km/l then had the service and it has gone down and still is?

Might ask them when she goes back for plug change, filter and brake pads.

RockCrusher · 03-02-2023, 05:20 PM

Quote:

Originally Posted by 3t3p

Manual.

She did have an oil change on arrival to the country.

5W-30 I'm sure is what he said was put in.

Only other change is going 255/35 to 275/35. But when those were brand new I actually had 11kml/l. Then it stabilised to 10km/l then had the service and it has gone down and still is?

Might ask them when she goes back for plug change, filter and brake pads.

You can check the engine air filter. Two times -- 2 different cars -- I let the air filter go too long. Just lost track of time. One car (Boxster) I changed the filter myself. Took the old filter turned it upside down and smacked it on the sidewall. Oh the amount of stuff that was on the sidewalk... And not surprisingly the engine ran better after a new filter was installed. I didn't bother with gas mileage checking but it wouldn't surprise me it was better.

Second car was my Dodge Hellcat. This I had done at the dealer. Service advisor bought out the engine (and cabin) air filter. The engine air filter was particularly dirty. Makes sense. Supercharged engine needs lots of air and the filter has its work cut out for it.

Oh, filter had 27K miles on it. Think Dodge called for at least checking the filter every 20K miles.

And as with the Boxster so too with the Hellcat. Driving the car home and throttle response was better. New air filter made a difference.

3t3p · 03-03-2023, 04:00 PM

She's had the air filter and spark plugs done now, swear can hear more turbo spool
Not had a chance to get on it as got new brake pads too and they need gentle bedding in at first.

I did ask them and they said efficiency should be better after a service of course!
Maybe it's the bigger heavier tyres?

02-03-2023, 03:30 AM	#1
3t3p Major 455 Rep 1,389 Posts Drives: M2 Join Date: May 2018 Location: NZ iTrader: (0)	Car serviced and now mpg is lower?! Had my car serviced, really only an oil change and they ran injector cleaner through. First tank of petrol didn't notice much but then thought the car seemed very happy and I'm waiting for my plugs and engine air filter to arrive. Only other variable is it's become warmer. My km per litre has dropped from 10 or so in town to 8-8.5?! The right foot is about the same. Am I going nuts?!
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02-03-2023, 01:40 PM	#2
Moloc Enlisted Member 80 Rep 45 Posts Drives: BMW M2 Join Date: May 2022 Location: Ontario iTrader: (0)	I'm running in the 8's with spirited driving around town. Got it down to 7.8 once. Last edited by Moloc; 02-04-2023 at 03:41 PM..
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02-03-2023, 05:17 PM	#3
agent_orange Private First Class 152 Rep 127 Posts Drives: 2014 F25 X3 30d, 2021 F87 M2C Join Date: Apr 2020 Location: Australia iTrader: (0)	First oil change in NZ after moving from the UK? What oil did they use? BMW Australia uses TwinPower M 0W40 LL-01 for the turbo M cars, not the thinner stuff used in north America. May be the same with NZ vs UK? Wouldn't make as much of a different to fuel economy as what you are seeing I would have thought though.
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02-04-2023, 01:46 AM	#4
///M TOWN . 16541 Rep 8,425 Posts Drives: M GmbH Join Date: Aug 2018 Location: North America iTrader: (0) Garage List 2018 M2 [8.82]	OP…. What transmission do you have… ⁉️ __________________ ///
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02-08-2023, 03:58 AM	#5
3t3p Major 455 Rep 1,389 Posts Drives: M2 Join Date: May 2018 Location: NZ iTrader: (0)	Manual. She did have an oil change on arrival to the country. 5W-30 I'm sure is what he said was put in. Only other change is going 255/35 to 275/35. But when those were brand new I actually had 11kml/l. Then it stabilised to 10km/l then had the service and it has gone down and still is? Might ask them when she goes back for plug change, filter and brake pads.
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03-03-2023, 04:00 PM	#7
3t3p Major 455 Rep 1,389 Posts Drives: M2 Join Date: May 2018 Location: NZ iTrader: (0)	She's had the air filter and spark plugs done now, swear can hear more turbo spool Not had a chance to get on it as got new brake pads too and they need gentle bedding in at first. I did ask them and they said efficiency should be better after a service of course! Maybe it's the bigger heavier tyres?
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