Fuel Consumption Worries

Need technical Q/A then you're in the right place

Moderator: martauto

Post Reply
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 10, 2008 10:15 am

Im only getting around 50 miles with £20 worth of fuel (£1.10 per litre) ??

Thats around 10 mile per the gallon in my 2.7?

Im currenlty using a 2.5bar fpr, which needs to be changed to a 3ar.

What/where should i be looking to get this sorted or is this what is expected???

:cry:
Image
Ziggy
E30 Zone Team Member
E30 Zone Team Member
Posts: 11534
Joined: Mon Jan 10, 2005 11:00 pm
Location: floating round my tin can...

Fri Oct 10, 2008 10:20 am

That's certainly not what you should be expecting. Should be high 20s or more, not 12MPG!
What engine setup is it, & what management are you running?
E30 in need of wiring loom smoke since April '11...
sunnyE30
E30 Zone Newbie
E30 Zone Newbie
Posts: 71
Joined: Wed Jan 23, 2008 11:00 pm
Location: West London

Fri Oct 10, 2008 10:21 am

Just sell it mate thats the best option :D
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 10, 2008 10:47 am

Ziggy wrote:That's certainly not what you should be expecting. Should be high 20s or more, not 12MPG!
What engine setup is it, & what management are you running?
The engine was from a genuine Hartge H27, I didnt do anything else to it (internaly).

Also running the original ECU
Image
Theo
Old Skooler
Old Skooler
Posts: 10735
Joined: Wed Jun 01, 2005 11:00 pm
Location: Kent

Fri Oct 10, 2008 10:52 am

You have to be a bit of a cheapskate to use a 2.5bar fpr on an engine like this :roll:

10mpg is truly awful, are you sure you don't have a quite sizeable fuel leak?
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 10, 2008 11:01 am

Theo325 wrote:You have to be a bit of a cheapskate to use a 2.5bar fpr on an engine like this :roll:

10mpg is truly awful, are you sure you don't have a quite sizeable fuel leak?
The engine came with one of thjose FSE boost valves which i took off straight away and replaced it with what i had on my B20.

I have been meaning to change this to a 3 bar. :o:

Fuel tank is standard?
Image
SPADGE
Married to the E30 Zone
Married to the E30 Zone
Posts: 7373
Joined: Wed Aug 09, 2006 11:00 pm
Location: Milton Keynes, Bucks

Fri Oct 10, 2008 11:11 am

Its a 5 minute jpb to replace the fpr so why not use your time to do that rather than waste it typing out about a problem that won't go away until the engine is running the correct components :?
Engine conversions, Auto to manual conversions, parts, servicing etc etc... For anything e30 call 07718 901737
Theo
Old Skooler
Old Skooler
Posts: 10735
Joined: Wed Jun 01, 2005 11:00 pm
Location: Kent

Fri Oct 10, 2008 11:13 am

Have you checked for fuel leaks? Start the car up and let it idle and have a good look round the engine bay where the fuel hose connections are. Also check round the fuel tank where there are any fuel connections.

I suppose the fuel consumption is never going to be great living in West London as there's so much stopping and starting and it changes in engine load which increase fuel consumption.

BTW, if you need an 3bar FPR, I have one which you can have for £13 posted.
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 10, 2008 11:27 am

Theo325 wrote:Have you checked for fuel leaks? Start the car up and let it idle and have a good look round the engine bay where the fuel hose connections are. Also check round the fuel tank where there are any fuel connections.

I suppose the fuel consumption is never going to be great living in West London as there's so much stopping and starting and it changes in engine load which increase fuel consumption.

BTW, if you need an 3bar FPR, I have one which you can have for £13 posted.
There is a brand new fuel tank and fuel hoses on the car which was done a month ago for MOT

running a 2.5 bar fpr wouldnt cause it to consume more fuel would it?

Paypal cool?
Image
Theo
Old Skooler
Old Skooler
Posts: 10735
Joined: Wed Jun 01, 2005 11:00 pm
Location: Kent

Fri Oct 10, 2008 11:41 am

I wouldn't have thought that the 2.5bar FPR would lead to increased fuel consumption, but it will definitely want changing.
sunnyE30
E30 Zone Newbie
E30 Zone Newbie
Posts: 71
Joined: Wed Jan 23, 2008 11:00 pm
Location: West London

Fri Oct 10, 2008 12:17 pm

SPADGE wrote:Its a 5 minute jpb to replace the fpr so why not use your time to do that rather than waste it typing out about a problem that won't go away until the engine is running the correct components :?

:D he is a time waster and a cheapskate always on the zone asking silly questions
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 10, 2008 12:38 pm

me being on the zone .... the car has come a long way!

By you writeing comments like that isnt wasting time and silly?

Dont let me start on the butcher jokes now sunny! winkeye
Image
sunnyE30
E30 Zone Newbie
E30 Zone Newbie
Posts: 71
Joined: Wed Jan 23, 2008 11:00 pm
Location: West London

Fri Oct 10, 2008 1:13 pm

:banana:
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Mon Oct 13, 2008 9:20 am

Guys,

After thinking about this over the weekend....

Could it be the gearbox that Im running?

The gearbox was left standard (320i) and the final drive is 3.91lsd?

I checked for any fuel leaks and could see any thing obvisous?
Image
maxfield
Old Skooler
Old Skooler
Posts: 15186
Joined: Sat Nov 26, 2005 11:00 pm
Location: Mansfield

Mon Oct 13, 2008 9:24 am

Doubt it's the gearbox. The gearbox ratos and the diff ratios are what came on the Tech 2 Sports.

Although I would expect the gear box to shit itself if your putting 2.7 torque through it.
Image
SPADGE
Married to the E30 Zone
Married to the E30 Zone
Posts: 7373
Joined: Wed Aug 09, 2006 11:00 pm
Location: Milton Keynes, Bucks

Mon Oct 13, 2008 9:25 am

The gearing you have wouldn't make it that bad on fuel no.
It'll either be running too rich or has a leak or both.
Engine conversions, Auto to manual conversions, parts, servicing etc etc... For anything e30 call 07718 901737
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Mon Oct 13, 2008 9:41 am

SPADGE wrote:The gearing you have wouldn't make it that bad on fuel no.
It'll either be running too rich or has a leak or both.
:cry:

what can cuase a engine to run rich? injectors?

When i ran the engine in i could smell alot of unburnt fuel but now it seems ok?

When i had the car MOT the guy was saying that the hyrdo carbons were high.
Image
SPADGE
Married to the E30 Zone
Married to the E30 Zone
Posts: 7373
Joined: Wed Aug 09, 2006 11:00 pm
Location: Milton Keynes, Bucks

Mon Oct 13, 2008 9:55 am

SilverShadow wrote:
SPADGE wrote:The gearing you have wouldn't make it that bad on fuel no.
It'll either be running too rich or has a leak or both.
:cry:

what can cuase a engine to run rich? injectors?

When i ran the engine in i could smell alot of unburnt fuel but now it seems ok?

When i had the car MOT the guy was saying that the hyrdo carbons were high.

A lot of things can cause an engine to run rich

Dodgy sensors, dodgy afm, throttle position sensor, ecu, map etc etc.......

High hydro carbons arn't a good sign.
Engine conversions, Auto to manual conversions, parts, servicing etc etc... For anything e30 call 07718 901737
TheDutch
E30 Zone Regular
E30 Zone Regular
Posts: 433
Joined: Sat Jan 15, 2005 11:00 pm

Mon Oct 13, 2008 10:20 am

Temperature sensor?
SPADGE
Married to the E30 Zone
Married to the E30 Zone
Posts: 7373
Joined: Wed Aug 09, 2006 11:00 pm
Location: Milton Keynes, Bucks

Mon Oct 13, 2008 10:39 am

TheDutch wrote:Temperature sensor?
A good starting point as if the engine things its always cold it'll over fuel it accordingly.
Engine conversions, Auto to manual conversions, parts, servicing etc etc... For anything e30 call 07718 901737
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Mon Oct 13, 2008 10:42 am

When i first start the car, the engine doesnt hold its rev and cut out so i have to press the the accelerator to warm it up.

but once the engine is warm the temp needle is in the middle.
Image
SPADGE
Married to the E30 Zone
Married to the E30 Zone
Posts: 7373
Joined: Wed Aug 09, 2006 11:00 pm
Location: Milton Keynes, Bucks

Mon Oct 13, 2008 10:45 am

SilverShadow wrote:When i first start the car, the engine doesnt hold its rev and cut out so i have to press the the accelerator to warm it up.

but once the engine is warm the temp needle is in the middle.
Will it idle when cold with the iscv un-plugged?
Engine conversions, Auto to manual conversions, parts, servicing etc etc... For anything e30 call 07718 901737
FlappySocks
E30 Zone Regular
E30 Zone Regular
Posts: 860
Joined: Sun Jan 22, 2006 11:00 pm
Location: Fareham, Hampshire
Contact:

Mon Oct 13, 2008 10:49 am

Check the blue temperature sensor. Easy to test, and one of the main causes of over fueling.
Check for air leaks.
Lastly a knackered Air Flow Meter.

Consider an aftermarket ECU with wideband sensor.
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Mon Oct 13, 2008 10:52 am

Boys i will check for these: icv, blue temp sensor

How is the best was to test the blue sensor?
Image
User avatar
AlexBaur325
E30 Zone Regular
E30 Zone Regular
Posts: 685
Joined: Fri Nov 02, 2007 11:00 pm

Mon Oct 13, 2008 6:16 pm

Just sell it mate thats the best option
wouldnt do that at the mo... :roll:
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 17, 2008 6:34 pm

SPADGE wrote:Will it idle when cold with the iscv un-plugged?
Just checked this, pulled the plug off the icv and started the engine and it idle'd.

Have i got a knckerd icv?
Image
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Fri Oct 17, 2008 10:54 pm

forgot to add the it did run a bit rough when i pulled the plug..
Image
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Sun Oct 19, 2008 12:06 am

anyone?
Image
StuBeeDoo
Engaged to the E30 Zone
Engaged to the E30 Zone
Posts: 6756
Joined: Sat Feb 05, 2005 11:00 pm
Location: Up My Own Arse

Sun Oct 19, 2008 8:02 am

SilverShadow wrote:Im only getting around 50 miles with £20 worth of fuel
Not exact science, that, is it? :roll:
Check the fuel consumption properly before you make assumptions like that.
This is why I no longer drive an E30......

Image
e30bmlover
Ac Schnitzer prophet
Ac Schnitzer prophet
Posts: 5352
Joined: Sun Sep 11, 2005 11:00 pm
Location: Playing on the ring road!!!

Sun Oct 19, 2008 12:18 pm

tbh i havent really noticed any difference when i put on the 3bar fpr...
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Thu Oct 23, 2008 2:13 pm

Guys

I changed the FPR over the weekend to a 3 bar and today I got 70miles from £20 (at £1.10 per litre), driving it a bit hard.

Runs much nicer and does not feel hesitant at all now!

Well happy!

:D
Image
SilverShadow
Hartge Crew
Posts: 1362
Joined: Sun Jan 16, 2005 11:00 pm
Location: London

Thu Oct 23, 2008 3:21 pm

e30bmlover wrote:tbh i havent really noticed any difference when i put on the 3bar fpr...
I've seen a massive difference! feels more smooth and free flow?

with the 3 bar Ive worked out that Im bnow getting 16mpg still not that great but better then 10! :mad:
Image
abelai
E30 Zone Regular
E30 Zone Regular
Posts: 848
Joined: Sat Aug 06, 2005 11:00 pm
Location: Cardiff

Thu Oct 23, 2008 7:27 pm

resitance 200-300ohms when hot
If I can't fix it I'll f**k it up so bad nobody can!!
Post Reply