Car runs badly when cold

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chu346
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Post Sat Nov 18, 2006 8:37 am

For some reason my car runs really bad when cold, but as soon as its up to temperature its fine. It idles ok but starts to die when the throttle is pressed and I start to drive. It's also using lots of fuel when cold and possibly a little more when warm :(

Any ideas guys, it's a 327i M20 engine.
ed325i
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Post Sat Nov 18, 2006 8:47 am

Could be the blue temp sensor.
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chu346
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Post Sat Nov 18, 2006 8:54 am

I thought that causes the engine to over fuel when warm?
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Brianmoooore
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Post Sat Nov 18, 2006 10:07 am

chu346 wrote:I thought that causes the engine to over fuel when warm?
It does, or it can give your symtoms. Depends what's gone wrong with it.
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chu346
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Post Sat Nov 18, 2006 10:36 am

It's bust :lol:

I'll try a new one today. I only replaced this a year ago :cry:

Cheers
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Brianmoooore
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Post Sat Nov 18, 2006 10:46 am

Measure the cold resistance of your sensor. Would expect something like 3500 - 4000 ohms this time of year.
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chu346
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Post Sat Nov 18, 2006 11:15 am

I got about 4500?

Is that too much.
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Brianmoooore
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Post Sat Nov 18, 2006 12:57 pm

Sounds highish, but the temp up North where you are is probably less than I usually ever see.
In any case , it would have to be much lower (1000 ohms or less) to cause your problems. May be worth posting a normal running temp reading as well.
Next suggestion is to hunt for inlet side air leaks.