I got my 1.8 TSI SC in May this year, was told the MPG would get better after the car has done a few thousand miles. For the first few thousand miles of my car my average MPG was 37. But after about 3000 miles I am now getting 31 MPG even though my engine has passed its break in period and I am driving more economical compared to when I first got the car. How has my MPG gotten worse? My tyre pressure is fine I check this every week, just not sure how my MPG isn't getting better.
1.8 TSI Fuel economy worse after engine break in?
- Thread starter RJay
- Start date
Sounds odd. My 1.8 returned 39 on long term average over the 2 yrs I had it.
What fuel are you using? Have you changed?
Log mileage when you fill up for several tanks and work it out manually just to check it’s not an issue with the onboard computer - this can be adjusted it it’s inaccurate.
What fuel are you using? Have you changed?
Log mileage when you fill up for several tanks and work it out manually just to check it’s not an issue with the onboard computer - this can be adjusted it it’s inaccurate.
A 6 mpg drop is quite large. I have the VAG 1.8 petrol engine in my VW and I average around 40mpg.
How are you measuring your fuel consumption? Are you calculating it manually or relying on the car’s fuel computer?
Many factors can affect fuel consumption and one of more of the factors below could have changed since you were getting 37 mpg and could be influencing your fuel consumption;
Changing the brand of fuel you use
Traffic conditions and increase in traffic density
Travelling at different times of the day now compared to when you were getting 37 mpg
Change in weather conditions
A change in the mix of driving you do between built up areas and rural / A roads / motorway
A change in mix of driving between long and short journeys
Other people driving your car (partner, kids)
Increased use of electrical equipment in the car during winter months
I suspect if you raised the drop in mpg with Seat, they’d say that 31 is still acceptable for the 1.8 engine and many factors could influence overall fuel consumption. As trebor suggests, manually monitor your fuel consumption over a longer period which should give a more representative view of the true mpg you’re getting.
How are you measuring your fuel consumption? Are you calculating it manually or relying on the car’s fuel computer?
Many factors can affect fuel consumption and one of more of the factors below could have changed since you were getting 37 mpg and could be influencing your fuel consumption;
Changing the brand of fuel you use
Traffic conditions and increase in traffic density
Travelling at different times of the day now compared to when you were getting 37 mpg
Change in weather conditions
A change in the mix of driving you do between built up areas and rural / A roads / motorway
A change in mix of driving between long and short journeys
Other people driving your car (partner, kids)
Increased use of electrical equipment in the car during winter months
I suspect if you raised the drop in mpg with Seat, they’d say that 31 is still acceptable for the 1.8 engine and many factors could influence overall fuel consumption. As trebor suggests, manually monitor your fuel consumption over a longer period which should give a more representative view of the true mpg you’re getting.
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Just my 2 cents, my usual Sunday morning journey from East London to West London, usually yields 50-52mpg (best was 58.5mpg) in weather around the 15-20 degrees mark.
Yesterday, despite having less traffic, due to 6 degrees temp, my car could only muster 47mpg.
Also from experience, Shell Vpower gave both my Seats better fuel consumption (at least on the trip computer).
* I did use the heater yesterday though, for most of the journey, maybe that's why...
Yesterday, despite having less traffic, due to 6 degrees temp, my car could only muster 47mpg.
Also from experience, Shell Vpower gave both my Seats better fuel consumption (at least on the trip computer).
* I did use the heater yesterday though, for most of the journey, maybe that's why...
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Thanks for all the reply guys. theoldboy I am going by what the trip computer says, not using an app.
SRGTD - I use either Sainsburys or Shell fuel just depends where I am. I drive the same roads and have the same driving style, trying not to put the foot down!! It's just recently that my economy has dropped, find it strange since I hardly rev over 3000rpm and take it easy. Would expect to get better than 31mpg! I always put £20 of fuel when I fill up and I also reset the miles, I tend to get 120-130 miles out off £20.
SRGTD - I use either Sainsburys or Shell fuel just depends where I am. I drive the same roads and have the same driving style, trying not to put the foot down!! It's just recently that my economy has dropped, find it strange since I hardly rev over 3000rpm and take it easy. Would expect to get better than 31mpg! I always put £20 of fuel when I fill up and I also reset the miles, I tend to get 120-130 miles out off £20.
May just be the weather then. On my 15 mike commute I do notice a 5 mpg drop when the weather is colder. Colder block to heat up, oil thicker, heating and demister and lights on in the car probably air on too. On a commute type journey this is the sort of impact a frosty morning can have. Evens out more on longer trips obviously. My commute in my cupra has been circa 35mpg, now seeing it dip to 30 as it’s colder, lights on to and from work etc.
I never rev mine past 3k hee hee. My DSG has a 'bad' habit of changing gear around or under 2k. I normally use Esso or Shell regular 95 or Tesco Momentum 99.
On a 1.0TSI, £20 gets me around 170-180 miles. of course we are not comparing like for like.
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Why would temperate cold weather make the car less efficient?
The engine warms up to operating temperature within minutes and the heater uses excess not extra energy.
Is there a mechanism for warming the air entering the engine intake?
The engine warms up to operating temperature within minutes and the heater uses excess not extra energy.
Is there a mechanism for warming the air entering the engine intake?
Have a read of the article at the link below;
https://www.holtsauto.com/redex/news/how-cold-temperatures-affect-car-fuel/
Although it is focusing on the effects of winter weather, some of the points made will also be relevant if the weather is cold at this time of year.
I had a 1.8 FR manual for nearly 4 years and got around 37 mpg for the whole 4years from new. This was fairly constant for normal driving on mixed roads. On longer journeys when I used to drive up to Scotland from Nottinghamshire I averaged at around 43 mpg. I often used Shell V Power or Tesco Momentum just to keep the engine in good condition, but to be quite honest it ran just as well and just got the same mpg with standard Jet petrol from my local garage in the village.
I now have a VW Golf 1.4 GT Edition DSG and I’m generally getting around 47 mpg most of the time. That extra 10 mpg is making a big difference in the number of times I have to fill up.
I now have a VW Golf 1.4 GT Edition DSG and I’m generally getting around 47 mpg most of the time. That extra 10 mpg is making a big difference in the number of times I have to fill up.
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