316 mpg??

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Sambe30
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Post Wed Jan 28, 2015 7:49 pm

Hi I have a 1990 316, from what I have read it is a m10 carb engine. Driving sensibly over the last few tanks I have worked out my mpg and it avereges out at about 15mpg. Is this normall? Or could it be possible I have a fuel leak somewhere?[/i]
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Post Wed Jan 28, 2015 8:24 pm

15mpg is way too low. Are you measuring it by brimming the tank?
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Post Wed Jan 28, 2015 8:27 pm

Sambe30 wrote:Hi I have a 1990 316, from what I have read it is a m10 carb engine. [/i]
Really? :mad:
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Sambe30
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Post Wed Jan 28, 2015 8:33 pm

Grrrrmachine, the first few were then the next few were half tanks. And Daimlerman I do not follow?
daimlerman
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Post Wed Jan 28, 2015 8:36 pm

Sambe30 wrote:Grrrrmachine, the first few were then the next few were half tanks. And Daimlerman I do not follow?
IF you own a 1990 316,it should have an M40 injection engine.....
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Sambe30
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Post Wed Jan 28, 2015 8:46 pm

You are correct, sorry my mistake!
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Sambe30
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Post Wed Jan 28, 2015 8:46 pm

It still doesn't help with 15-17mpg
daimlerman
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Post Wed Jan 28, 2015 8:47 pm

I would suggest that you check the blue temperature sensor for correct operation.
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Sambe30
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Post Wed Jan 28, 2015 8:51 pm

Where would I find that? And what do you mean by that could it be broken?
TPS
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Post Wed Jan 28, 2015 8:52 pm

Underneath the Inlet Manifold
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JF008
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Post Wed Jan 28, 2015 8:56 pm

http://www.e30zone.net/e30zonewiki/index.php/Blue_Plug , its easy to do yourself. I changed mine on a different engine and it helped the MPG a bit.

JF
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Post Wed Jan 28, 2015 8:57 pm

i was getting shite mpg put in a 2.5 now its even shitter but sounds much better!
daimlerman
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Post Wed Jan 28, 2015 8:58 pm

Sambe30 wrote:Where would I find that? And what do you mean by that could it be broken?
This widget tells the engine ECU the temperature of the cylinder head,so if the ECU thinks the engine is always cold,the ECU tells the injectors to inject more petrol.....

The M40 engined 316i that I ran a few years back usually returned about 33mpg,but it's worst tankfull was about 18mpg,when 'er indoors used it for a month for her home to work trip of .8 of a mile each way...the poor thing never reached running temperature!
TPS
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Post Wed Jan 28, 2015 9:04 pm

My 318 auto., MPG is shocking, My 325 auto. is only slightly worse! Done loads to it, still awful.
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Sambe30
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Post Wed Jan 28, 2015 9:33 pm

Where can i get the sensor anyone got a link?
TPS
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Post Wed Jan 28, 2015 9:37 pm

Car Parts 4 Less
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Sambe30
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Post Wed Jan 28, 2015 9:43 pm

TPS
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Post Wed Jan 28, 2015 9:44 pm

Thats the one
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Sambe30
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Post Wed Jan 28, 2015 9:45 pm

Thank you very much TPS, and everyone else. I will order one of them and try that, if that doesn't work, back to the drawing board.
Grrrmachine
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Post Wed Jan 28, 2015 10:28 pm

NO! DON'T just order a blue plug and swap it over.

TEST the existing one first, using the guide in the Wiki, and then replace if necessary. Otherwise, leave it alone.
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Sambe30
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Post Wed Jan 28, 2015 10:42 pm

What bit is the blue plug? Have you got a link mate?
Grrrmachine
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Post Wed Jan 28, 2015 10:43 pm

JF008 posted a link to the article in question in this thread, two hours ago.
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Post Thu Jan 29, 2015 10:01 am

My 325i manual cabby gives exactly the same MPG that my 318i auto moredoor used to give me. My cabby gives me a return of around 25 MPG on my daily commute to work.

When I first purchased the 318i, I was getting around 18 MPG continuously.

Got the TPS sorted, and replaced the exhaust which was rotten all around the straps, and the MPG greatly improved.

Test the Blue Temp Sensor before replacing it, as it could be something else causing it to return such low MPG figures.