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Discussion Starter · #1 ·
Just wandering what tyre pressures you guys run , mine have been 42-43 since I had it , I presume this is for economy, the app says recommended 32 though ? Currently getting 42-45 mpg not too bad for semi back lanes I use , but find car back end can skip on hard corners , I assume lower pressure will grip more but suffer economy?
 

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What size tyres do you have? I assume you have the standard 225 / 45 / R17? If so, the tyre pressues should be as follows:

  • Comfort: 32 front 32 rear
    Eco: 39 front 39 rear
    Full Load: 36 front 39 rear

42 - 43 sounds a bit high and is probably from when the vehicle was transported. They overinflate the tyres to reduce the amount the car bounces about on the transporter

I personally, never find the Eco setting to be the most comfortable so I send to go for something in between Comfort and Eco. In my current car, I find 35 front and rear is about right. I find the higher tyre pressures result in a lack of grip around corners. I don't know if the app will like that midway tyre pressure.
 

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My tyres (Bridgestone Turanza 17") were up at about 39 all round and it just wasn't as comfy or as grippy as I expected.

However, I've now lowered mine to the 32psi setting all round and the car is much more composed and the steering feels a tad heavier too. Can't imagine it would make that much difference to the fuel economy but the car will definitely feel better.
 

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I'd been running mine at the eco setting to try and get the best fuel economy, but I've just dropped them back down to comfort. We'll see if it makes much difference to the fuel economy, it can't get much worse!
 

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Discussion Starter · #5 ·
I've seen the eco setting , now does that automatically change when you alter the tyre pressure ? Sorry to seem bone ;)
 

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Mine have been at 39psi since I picked it up last week

1900sr said:
I'd been running mine at the eco setting to try and get the best fuel economy, but I've just dropped them back down to comfort. We'll see if it makes much difference to the fuel economy, it can't get much worse!
What sort of fuel economy are you getting 1900sr? I have the same engine, love it and the car but the best I have got is 37mpg.

I spotted it mentions in the manual that the fuel economy wont be the best until the car has been run in for a bit so I prob have to wait.
 

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ZappyPayload said:
Mine have been at 39psi since I picked it up last week

1900sr said:
I'd been running mine at the eco setting to try and get the best fuel economy, but I've just dropped them back down to comfort. We'll see if it makes much difference to the fuel economy, it can't get much worse!
What sort of fuel economy are you getting 1900sr? I have the same engine, love it and the car but the best I have got is 37mpg.

I spotted it mentions in the manual that the fuel economy wont be the best until the car has been run in for a bit so I prob have to wait.
Maybe I should stop moaning, I've been getting an indicated 43-45mpg pretty much since it was new. I think the computer is over reading by a couple of mpg. I did see 51mpg on trip 2 when I reset it joining the A1 at Grantham, and checked at the end of the A1 dual carriageway in London, but the average was still 45 for the tank.
 

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gunswills said:
I've seen the eco setting , now does that automatically change when you alter the tyre pressure ? Sorry to seem bone ;)
You need to tell the car from the info system, if you don't it won't cause much of a problem but the car won't tell you the tyre has lost pressure until it drops below the 32psi setting. The app will still tell you that 32psi is recommended though.
 

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Discussion Starter · #9 ·
Just noticed my 3 settings are , light , Eco , max , does that equate to the comfort , Eco , full load ? , gonna drop em to 35 tmrw and throw a few hundred miles on and see how we fair ?
 

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I found 35 to be best in my current car - it to has 32 as comfort and 39 as Eco. I did try 36 for a while but found it to be too firm for my liking. You may need to play around with different pressures to work out what is best for you.
 

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Discussion Starter · #12 ·
Wow car transformed , dropped the pressures to 35 all round and what a difference in the ride , lot more comfortable and of course a lot more grip ;) , I also reset the trip and mpg screen and after around 150 mile of mixed driving , it's still retaining 42mpg , quite happy with that ;)
 

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somervillearron said:
my 1.6 cdti came with 40psi all round i was getting 47 mpg max

i dropped it down to 35 front 32 rear and the grip is now great and i get between 55 and 62 mpg and i never go near a motorway!
You'll find that the increased fuel economy wasn't as a result of you deflating your tires. :D

Mine too (1.6CDTi Elite) was doing poor-ish economy (~42mpg) until after about 500 miles, when the engine management unit settled down and I started getting ~56mpg. I did a 200 mile (60/40 - M-way/H-way) trip and got 62mpg and did have a little bit of a heavy right foot on that trip, I kept having to rest it on the accelerator.

Nice to see another owner getting comparable results.

Just checked my tyre pressures and they're 38psi front/ 39psi rear. I will however, drop my pressures a little and see if comfort, ride quality and handling improves and doesn't affect fuel economy too much.

Thanks for the heads-up guys!
 

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Looks like i should drop my pressures. Did feel the car was rather rough on the roads and not smooth. I will deflate them to 35 like you guys said and see how that goes. Im guessing they are that pressure for transport to stop the car moving on the transporter.
 

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Hiya! My new 1.6 CDTi Automatic was delivered Monday - Done about 300 miles so far and got a reading of about 67mpg on the computer for 80 mile motorway trip I did - Seems a little high but if I'm getting 10mpg less than that i'd still be happy.

My tyre pressures are all around the 38psi mark, as delivered. Once thing I did notice though is that my oil life was delivered at 49%, whats that about?

I have a techline and don't have OnStar so that reading is from the on board computer.
 

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Skyfall said:
Hiya! My new 1.6 CDTi Automatic was delivered Monday - Done about 300 miles so far and got a reading of about 67mpg on the computer for 80 mile motorway trip I did - Seems a little high but if I'm getting 10mpg less than that i'd still be happy.

My tyre pressures are all around the 38psi mark, as delivered. Once thing I did notice though is that my oil life was delivered at 49%, whats that about?

I have a techline and don't have OnStar so that reading is from the on board computer.
The oil life is based off a timer which should be reset when the car goes for Pre-Delivery Inspection. Although it seems weird that it's so low. I can't imagine your car was sat in a field for 6 months! You should be fine to reset it yourself given that it's brand new.
 

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Dropped min to 30 psi to see if I could achieve more comfort on bad roads ....a marked improvement again so quiet. .and rides superbly...I do have premecy 3s on and not bridgestone so softer rubber on the road ...32 psi is for 3 people and normally only one in mine so gave it a go 2 psi under ....I am also achieving 38..to 40 and close to 50 on a run...but am steady driver ..and not a speed freak.
 
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