MPG & Speed

[smilson]

Did a rough estimate of the MPG I have been getting out of my 1999 Nissan Terrano 2 2.7 TDI SE. And it is coming out at aroung 22/24 mpg. Don't drive like miss Daisy but also don't drive it like I have stolen it done a couple of long runs since I have had it but mainly short trips aroung town.

Just wondered if this is about right but does seem a bit rich. Also had the truck fully serviced when I got it as it was driving real lumpy and slow.

Second thing is I took it down the motor way today and put the pedal to the floor... On the way with a head wind was struggling to get past 75mph and on the way back was struggling to get 85mph with a strong backwind. Is this about right or could this be linked in with my poor MPG?

One thing I need to have done is I suspect the clutch bearing has gone as very noisy when I lift my clutch even when not in gear. Am looking at getting the full kit changed as soon as I have the money. But I don't think that would impact on the speed and MPG performance??

Cheers for any adive :thumb2

 

[eurag]

If your doing 70-80mph then i am not suprised your mpg is poor. Remember you are driving something with the aerodynamics of a brick. This has a greater effect the faster you travel. I normally sit at about 60mph and get 28-31 mpg.

 

[supergnome]

What he said.David.

 

[JMAY]

Hi there, I get 25mpg on average but tend not to work it out to often as i know its not good and accept it.
You truck should pull to 100 without a problem, they fairly shift with foot on the floor.
On a long run to devon doing 80-85 i once got 27 average mpg.
Cheers

 

[arcascomp]

If it's dragging its heels then it's either not getting enough fuel or air or something is holding her back physically (apart from the shape of it!)

Check the old mini filter in/under the banjo bolt, not everyone has one, but if it's there it might be a bit blocked and be causing a restriction in fuel flow. Other fuel issues could be rusting/restricted flow within the fuel lines, check for any leaks under the rear axle, quite common on these.

Also worth greasing the front hubs - see downloads section - as there could be excess friction there and you might even find a minor brake binding going on. Both will cause increase in fuel usage.

Yours has the intercooler so started life with 25 more horses under the bonnet than mine and my old gal will lift her skirts and hit 90 these days, but I can almost hear the fuel being sucked away and see the gauge go down when I do that (on private roads, obviously!).

 

[smilson]

If your doing 70-80mph then i am not suprised your mpg is poor. Remember you are driving something with the aerodynamics of a brick. This has a greater effect the faster you travel. I normally sit at about 60mph and get 28-31 mpg.

Yeah I normally drive sensible was just checking what the top speed was etc as the car seems to have lost some power.

So my MPG is with driving sensible and yesterdays motorway driving was not put into the equation

 

[smilson]

Hi there, I get 25mpg on average but tend not to work it out to often as i know its not good and accept it.
You truck should pull to 100 without a problem, they fairly shift with foot on the floor.
On a long run to devon doing 80-85 i once got 27 average mpg.
Cheers

Yeah thats acceptable then Just didnt want to ignore it and find out that if I changed the "flugal valve" etc I would be getting better mpg and had just thrown a lot of money down the drain for not asking a simple question.

 

[terranobreakershropshire]

it should pull more than that top end. banjo filter first off. my old tdi used to be about 18-20 towing 3 ton and 26ish driving it hard normally.

clutch bearing noisy when clutch pressed, more likely input shaft ratling on box - just ignore it, its a tdi thing!

 

[smilson]

it should pull more than that top end. banjo filter first off. my old tdi used to be about 18-20 towing 3 ton and 26ish driving it hard normally.

clutch bearing noisy when clutch pressed, more likely input shaft ratling on box - just ignore it, its a tdi thing!

Is it best just to leave it till it fails then? Going to cost me around £300 to get it sorted and not money I want to spend lol.

The noise is... When I put my clutch down its fine when I lift clutch even out of gear it rattles... Been told its like diesel knock... Noise seems to get worse when the car is warm and been on a run.

Also seems to be a bit more noise when driving sounds and feels like the engine is vibrating near the cab/behind dash.

Cheers

 

[(RIP) PLANK]

It was suggested a while ago on here (can't remember who sorry) that keeping your revs below 3000 improved economy. I have tried this and it seems to work :thumb2

 

[smilson]

Removed banjo filter and it looked clean as a whistle.

Cleaned out with turps and then boiling water.

Replaced and took it for a little drive.

Seemed to pick up a lot better and at 70MPH was almost 500 rpm lower than before.

Will need to take it for a longer drive and record some MPG driving again to see if there is any improvement on MPG.

Thanks for the help guys.

Also took the car to my mates garage who was going to do the clutch bearing etc and he said the car is fairly quite for a big diesel. Maybe it was just me being new to this kind of car

 

[eurag]

Seemed to pick up a lot better and at 70MPH was almost 500 rpm lower than before.

Not possible unless the clutch was slipping. The speed-rpm ratio is fixed unless you change the gearing or wheel/tyre size.

 

[Lazy-Ferret]

is it an automatic?

 

[eurag]

clutch bearing was mentioned in the OP

 

[briggie]

just out of interest , has anyone tried driiving exactly to the speed limit ,and following road laws exactly ? ...... then are overtaken like you are going backwards by some idiot and have abuse hurled at you

 

[rustic]

My 17 year old 2.7 td is still capable or speeds greater than 93, shown on the GPS on a private road of course. On longer flatter sections it has been known to get to the ton+
It was a bit sluggish the week before due to short journeys, so some injector cleaner, red line it in all gears and blow out the cobwebs, now the engine is quieter and runs more smoothly.
I still haven't removed the mini filter from new either.

So yours probably needs a good thrash, red lining it in the lower gears works for mine anyway.

The Tdi should get to the ton+ when running well

BUT you will need a diesel tanker along side to refuel though, at these speeds.:doh:doh

 

[smilson]

Maybe I am mistaken with the revs then but it did seem less work to get to speed. I assumed that with the little filter blocked it would be working harder to do what needs to be done due to fuel restriction.

 

[(RIP) PLANK]

Maybe I am mistaken with the revs then but it did seem less work to get to speed. I assumed that with the little filter blocked it would be working harder to do what needs to be done due to fuel restriction.

Revving faster could have been due to the clutch slipping. what mileage has it done?

 

[smilson]

just out of interest , has anyone tried driiving exactly to the speed limit ,and following road laws exactly ? ...... then are overtaken like you are going backwards by some idiot and have abuse hurled at you

Normally I drive very sensibily due to the fact I got the truck for the extra seats due to a large family (ie car full of kids)... Was just "testing" the speed thing due to the car seeming to be a bit slugish and slow so wanted to test the speed due to low MPG, then come on here and ask for advice

 

[smilson]

Revving faster could have been due to the clutch slipping. what mileage has it done?

Just over 120k but clutch seems fine apart from I can feel vibrations in the pedal and the extra noise it makes when clutch depressed.