mpg on p38 deisel

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
wreckhunter

wreckhunter

Active Member
Posts
309
Location
SOUTH WALES
I'd be interested to know what mpg people are getting from manual p38 deisels,I've been thinking of replacing my 200tdi which manages 28mpg with a p38 but was taliking to somebody the other day who says he's lucky to get 20mpg out of his.If this is the case it won't be any good for me as i do quite a lot of mileage.
 
mine was chipped and averaged round town 25-27 and anything upto 36-38 on mota way depending how it was driven
 
getting about 26 mpg on short runs between home and work, (5 miles, lots of junctions, stop start), but motorway, getting 34-36mpg. Chipping could improve this slightly??
 
I had a manual DSE a couple of years ago. Averaged 22 with maybe 25 on a motorway cruising at 80-85ish. Towing a large Hobby caravan dropped it to 16-18. Wasn't greatly impressed overall with the economy. Or the gearbox. Engine was OK when spinning above 2000rpm but no torque below that as the turbo doesn't do a great deal below 2000rpm. Very smooth and quietish when you're cruising though so quite refined (being a 6cyl) for a diesel. I believe some of the add on performance chips can be quite beneficial though.
 
wreckhunter said:
I'd be interested to know what mpg people are getting from manual p38 deisels,I've been thinking of replacing my 200tdi which manages 28mpg with a p38 but was taliking to somebody the other day who says he's lucky to get 20mpg out of his.If this is the case it won't be any good for me as i do quite a lot of mileage.
Click to expand...

Around and about with out the aircon on I get 26 to 28mpg and 32 on the autoroute. Aircon on flat out in our current heatwave saps about 2mpg.
Towing my Hobby caravan, if I keep it down to 60mph it average 22mpg on a 2 week holiday in the UK. Uping it to 70mph drops it below 20mpg.
These are brim to brim figures not the decidedly optimistic computer read out figures.
The car is a P38 DHSE Auto with a PSI power box.

It's great compared to the JapCrap diesel I had before that would drop to 12mpg on the motorway with the same caravan and could barely manage 40mph on motorway inclines coming across France from Germany.
 
My DT gives anywhere up to 34 on the motorway, and around 24 around town. I'm in the middle of a trip to Ireland now and clocked just over 545 miles from a full tank before fuel light came on (Reading to Galway). That gives an average of 27.25 by my calculation.
 
Yeah, it's bog standard engine/mechanicals wise, and that milage was 5 up with 5x luggage. I've only had the car a few months and from the point of view of milage doing better than I expected.:D

Had a few other problems associated with the car having been left standing for quite a while before I bought it, e.g. sticking EAS valves (make sure you get an eas cable and software, beats paying L/R dealer everytime you have a problem and pays for itself the first time you use it), and a rad that blew apart from a waterpump failure (plastic impeller disintergrated, so made sure I got a replacement with a metal one), but now it's running very well and I'm really pleased with it, as I knew I would be once I'd sorted out the issues from the previous owners disinterest and lack of knowledge. (A Polish chap who said he'd bought it but then found it wasn't really suitable for delivering pizza around town!:doh:
 
Last edited:
Just chopped my softdash classic in for a DSE. I'm still towing the same twin axle caravan, weighing in at 1900kgs, but fuel consumption is lower than it was with the 300TDI auto. I used to get 25 mpg towing, but now I get between 19 - 20 mpg.

Mine is not chipped (yet) but I did manage 30 mpg on the A roads in Norfolk last week. Yes the P38 engine is revvier than the TDI but fuel consumption depends on your right foot.

Derek is right though you need to the revs up around 2000 to get any meaningful mpg out of this engine.

Alan
 
Seems to vary quite a lot between vehicles. I had a manual and could hardly get above 25, even taking it easy. Now I've got an auto and can easily get 32/33 out of it.

High 20's to low 30's should normally be possible from most unless you've got a heavy foot. Start driving it hard and it really drinks - though I've never got under 21 even when pushing it with a heavy trailer on the back, so I reckon someone who can't get into the 20's has a problem with the car, or he's doing traffic light grand prix's all day!

Matt
 
mmaddock said:
Seems to vary quite a lot between vehicles. I had a manual and could hardly get above 25, even taking it easy. Now I've got an auto and can easily get 32/33 out of it.

High 20's to low 30's should normally be possible from most unless you've got a heavy foot. Start driving it hard and it really drinks - though I've never got under 21 even when pushing it with a heavy trailer on the back, so I reckon someone who can't get into the 20's has a problem with the car, or he's doing traffic light grand prix's all day!

Matt
Click to expand...

I reckon a lot of the variation in mpg is between proper brim to brim checks and people quoting the hopelessly inaccurate calculated consumption figure from the computer:rolleyes::rolleyes::rolleyes:
According to the computer, mine does 27 to 29mpg around and about and up to 34 mpg on the autoroute. See my earlier post for the accurate figures:D:D:D
 
Datatek said:
I reckon a lot of the variation in mpg is between proper brim to brim checks and people quoting the hopelessly inaccurate calculated consumption figure from the computer:rolleyes::rolleyes::rolleyes:
According to the computer, mine does 27 to 29mpg around and about and up to 34 mpg on the autoroute. See my earlier post for the accurate figures:D:D:D
Click to expand...

Even if you accept that the computer figures are generally inaccurate, hence my miles/litres calculation, the one thing they do seem to show is that it is actually more fuel effective to run at higher revs, as others have said, mine certainly seems to do better mpg at 65 than at 55, a bit of a reverse on the usual theory.
 
kernowdragon said:
Even if you accept that the computer figures are generally inaccurate, hence my miles/litres calculation, the one thing they do seem to show is that it is actually more fuel effective to run at higher revs, as others have said, mine certainly seems to do better mpg at 65 than at 55, a bit of a reverse on the usual theory.
Click to expand...

With the auto, I suspect that it's more to do with speed than revs, the torque converter locks at just over 50mph and thats when the best fuel consumption figures start to appear. Running around and about, a lot of the time it's below lockup speed and the fuel is just being wasted in torque conveter slip. That doesn't answer why the manual version seems to do consistantly worse on fuel consumption tho.
I reckon engine efficiency is at it's peak at around 3000 rpm.
 
You must log in or register to reply here.

Similar threads

T
P38A P38 DSE Manual (non-EGR) No turbo boost
Replies
7
Views
793
Grrrrrr
Grrrrrr
G
P38 4.0 v8 Automatic goes into low range all on its own
Replies
9
Views
1K
Datatek
Datatek
P38 Monkey
P38 Side Step replacement
2
Replies
22
Views
3K
P38 Monkey
P38 Monkey
M
1998 P38 2.5 TD S.O.S!!
Replies
18
Views
2K
Datatek
Datatek
Rob4x40
L322 TD6 transmission adventures
Replies
13
Views
3K
badfluffy
badfluffy
Back
Top