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I've noticed over the past couple of weeks that I am not getting the same miles per same amount of fuel. Car seems to be running just the same though, but on starting up, more so from cold there would seem to be a strong smell of petrol. There isnt a smell when the car is stationary, overnight or anything but once started it starts to smell pretty bad for a few minutes.

Computer now seems to show nearer 17mpg as opposed to the usual 21 mpg or so

Any ideas or suggestions?

I'm thinking O2 sensor or something, what do you guys think...
 

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I don't know, as my car always had lower gas than this I never got more than 500 km with a tank. even with clean maf, no fault codes, new plugs and etc.
Can my O2 sensor be faulty too ???
From what I heard bad O2 should be showned on fault code (DIS). or am I wrong ??


plisken said:
I've noticed over the past couple of weeks that I am not getting the same miles per same amount of fuel. Car seems to be running just the same though, but on starting up, more so from cold there would seem to be a strong smell of petrol. There isnt a smell when the car is stationary, overnight or anything but once started it starts to smell pretty bad for a few minutes.

Computer now seems to show nearer 17mpg as opposed to the usual 21 mpg or so

Any ideas or suggestions?

I'm thinking O2 sensor or something, what do you guys think...
 

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upon cold start the petrol is pumped with high pressure -
check the petrol line under the car in front of the drivers seat (LHD-car) where the petrol-pipe-line is changing from pipe to rubber hose, with the years the rubber hose has a tendency to fail right there ( I had the same on my car, replaced rubber hose and cold-start-petrol-smell was gone !!!)
-
this will only happen during 'cold-start', there4 NO smell otherwise -
this is a common failure > just a thought !
brgds
Karl
 

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Smokestack said:
Funny, I've had 660 kms out of a tank in my 3.8 Touring!
You might have a bigger fuel tank, and your engine doesn't have to battle with the South American temps.
 

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plisken said:
I've noticed over the past couple of weeks that I am not getting the same miles per same amount of fuel. Car seems to be running just the same though, but on starting up, more so from cold there would seem to be a strong smell of petrol. There isnt a smell when the car is stationary, overnight or anything but once started it starts to smell pretty bad for a few minutes.

Computer now seems to show nearer 17mpg as opposed to the usual 21 mpg or so

Any ideas or suggestions?

I'm thinking O2 sensor or something, what do you guys think...
Ive only ever seen around 17mpg unless on a long run with a light foot,does this mean i have problems????? On a run 20-22 is about it:confused:
 

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Can someone tell me where the O2 sensor/s are located on the 3.6L '90 model.

Cheers
Dave
 

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Geach said:
Ive only ever seen around 17mpg unless on a long run with a light foot,does this mean i have problems????? On a run 20-22 is about it:confused:

Is it a 3.8? 5 speed?


The 6 speed 3.8's should get aorund 26-28 mpg on the motorway at 80-90mph - cough cough.

Round town can be anything from 18 to 23 depending upon driving style.

On the track expect single figures.

Best

M5 Powered
 

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M5 powered said:
Is it a 3.8? 5 speed?


The 6 speed 3.8's should get aorund 26-28 mpg on the motorway at 80-90mph - cough cough.

Round town can be anything from 18 to 23 depending upon driving style.

On the track expect single figures.

Best

M5 Powered
Its a 3.6,5 speed but does get driven,if thats the right word! I dont think i'm particulary hard on her but i dont like to hang around. Local driving is definately sub.18. I dont get to do alot of motorway work as the nearest bit is the bottom of the m5 and thats 110ish miles away before i start.from what i remember on my last 'long haul' trip at 80/90 mph 20-22mpg was the sort of figure i was acheiving. Its hard to say because holding a nice sensible speed on a dual carrigeway like that is always hampered by some muppet who wants too travel along at 50 in the outside lane so i end up constantly accelerating/deccellerating,which eats fuel!
 

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I too get 640 km/ 400miles on a motorway run and I think 320 miles on more urban runs although I never really do short ie less than 10 mile runs. After all she is made for the autobahn (and the Nurbergring) :blink: .


Pip
Ps Mine is a 3.6 1990
 

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OZ///M5 said:
Can someone tell me where the O2 sensor/s are located on the 3.6L '90 model.

Cheers
Dave
If memory serves it is close to the cat. Kind of hard to get at, you will either have to drop the exhaust some or have a stuby wrench.
 
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