Fuel econemy!

[plumb bob]

Hi all.

Since I had the head replaced, my fuel useage has increased by about 20%

It used to do 22mpg but now only does 18mpg.

At that kinda mileage I might as well out it and buy a range rover or any other petrol v8!

Anybody got any ideas as to why this could be and how it can be sorted??






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[drunkmonkeyboy]

perhaps its cos its going better so you are more tempted to put your foot down more hence the lower mpg. just my simple brain ruling out the simple answers untill someone with more knowledge comes to your rescue.
















ps i will ignore the LR comment!!!

[plumb bob]

No, unfortunately it doesn't go any better,( its never been that quick)and I don't drive it any different.
I have to drive at full throttle til I reach 30/40mph or I hold up traffic.

[BUSHWHACKER]

Hi all.

Since I had the head replaced, my fuel useage has increased by about 20%

It used to do 22mpg but now only does 18mpg.

At that kinda mileage I might as well out it and buy a range rover or any other petrol v8!

Anybody got any ideas as to why this could be and how it can be sorted??






.

Air filter OK?
I assume the pump timing is OK as you would have said the truck was running rough.
ECU been re-set?

[plumb bob]

I guess the mech had both batts disconnected for the two weeks it was in the garage, so that would reset the ECU?

If so how would that affect the fuel econ?

[BUSHWHACKER]

I guess the mech had both batts disconnected for the two weeks it was in the garage, so that would reset the ECU?

If so how would that affect the fuel econ?

Just thinking out loud really.

Is your engine an EFI?

[plumb bob]

Non EFI,
The engine seems to be running ok, apart from a strange rattle from top end at about 2500rpm, almost like a valve rattle. ( I assume stevo's heads come with new valves and springs etc?)

Also the exhaust has a slight leak somewhere between the manifold and first connection to main system, and I know 4mpg down aint much but when you start at 22mpg its quite a chunk to lose.

[BUSHWHACKER]

Non EFI,
The engine seems to be running ok, apart from a strange rattle from top end at about 2500rpm, almost like a valve rattle. ( I assume stevo's heads come with new valves and springs etc?)

Also the exhaust has a slight leak somewhere between the manifold and first connection to main system, and I know 4mpg down aint much but when you start at 22mpg its quite a chunk to lose.

You may need new or recond, injectors as you should have been getting beter mpg than 22 before.

[plumb bob]

I guess it wouldn't hurty to have new injectors, i'll ask the mech if he noticed the condition of them when he swapped them into the new head.

Surfs gotta go into garage to find exhaust leak and repair.

Is there anybody in SE UK that does rolling road tuning on these type of vehicles, and if so would that help??

[nero279]

I'm not sure, and i can't remember where in kent you are, but i have been told there's an aussie mech at chilham sports cars who is supposed to have done a lot of work of yotas both here and in aus, apparently more on landcruisers than surfs but may be worth a word. His name is Koo, apparently.

[Maverick]

You don't say how long ago you changed the head. Mine gave mpg figures that made me weep for the first couple thousand km, then it returned to its usual 20mpg.

[plumb bob]

I'm not sure, and i can't remember where in kent you are, but i have been told there's an aussie mech at chilham sports cars who is supposed to have done a lot of work of yotas both here and in aus, apparently more on landcruisers than surfs but may be worth a word. His name is Koo, apparently.

Hi Ian, I'm in Margate, so Chilham is not too far away ,I think I know Chilham sports cars, so I'll try popping in next time I'm in the area.Thanx.

[plumb bob]

You don't say how long ago you changed the head. Mine gave mpg figures that made me weep for the first couple thousand km, then it returned to its usual 20mpg.

Head was done about three weeks ago so I guess I've only done about two tanks, (500 miles).

Maybe it will settle down, I hope so, I can't really warrant driving a car that only does 18mpg, its just too expensive, but I do need transport for my dog.

[plumb bob]

Update

Well the increased fuel consumption isn't consumption at all its a leak that gets worse the higher the revs.

I've read most of the threads on fuel pump leaks and the general thing seems to be the top seal.

Nobody I've talked to around here seems to have a clue about surfs, and TonyN is just too far away ( unfortunately) so I'll have to have a think on what to do.

Mine is the non EFI pump ( therefore mechanical) which is apparently much harder to repair.
Does the pump have to be removed from the vehicle to replace this top seal???
Or can it be done in-situ??

[legendgamesmaster]

howe to know?

how did you find out it was a pump leak? mine has $$$$ MPG - wonder if its got a similar problem.