Cold no-start

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Andrew in Calgary
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Cold no-start

Post by Andrew in Calgary »

Running behind this morning thanks to my car that won't start, so not a lot of trouble-shooting thus far.

Engine cold, cranks fine, fuel pump running and fuel being pumped through the system but not yet sure if the injectors are firing. Gives a half-hearted almost-start when first cranked, but gives up shortly after that and just cranks without any evidence of ignition.

I know I can figure it out - I have enough tech info on hand and I am a mechanic afterall, but is there a likely culprit here I should look at first?
"There is nothing that a man can not make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." - Rio Sollway
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1st 5er
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Post by 1st 5er »

Being that I lack expert diagnostic capabilities, I'll just take a WAG;
Cold start relay or AFM connector.

Now I'll relax and await the professionals and hopefully learn something,
but more than that hopefully be able to remember it if/when the need arises.
Sherman

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Techboy
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Post by Techboy »

Check spark and injector pulse (with a node light) and let us know what you have or dont have.
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Andrew in Calgary
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Post by Andrew in Calgary »

I went out to the car this morning, asked it kindly to please start, hit the key and it jumped to life immediately. Gremlins I suppose.
"There is nothing that a man can not make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." - Rio Sollway
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Mike W.
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Post by Mike W. »

For future reference... It shouldn't be, but it has happened to me that I flooded it one time in cold weather. Anyway, if you even suspect it might be flooded, and it's unlikely, but possible, unplug the ECU in the glove compartment, with the key off of course. Then try and start it. If it's flooded, it will briefly fire up and rev for a couple of seconds, then die again. But that's ok, with the key off, plug the ECU back in. You have now burned off the excess gas that had it flooded, and warmed up the plugs just a little bit. It should start right up.
Mike W.



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Bob in San Jose
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Post by Bob in San Jose »

My previous 79 had this problem when it would get cold here. Living in Northern California that means the high 30's. I would just remove the fuse for the fuel pump and then follow Mike's routine.
I have owned 4 different e12's and this was the only one that exhibited this problem.
1980 528i 5 Speed
1988 535i 5 Speed
1995 540iA 5 Speed Auto
1980 528iA - Now Mike W's project car
Andrew in Calgary
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Post by Andrew in Calgary »

I'm fairly certain it was flooded. I'd let it sit for a couple of hours and it still wouldn't fire up but the next morning it lit off instantly. It needs a general tuning one of these days anyway and I suspect it's state of tune combined with the weather and my finicky ignition key conspired to leave me flooded.
"There is nothing that a man can not make a little worse and sell a little cheaper, and the people who consider price only are this man's lawful prey." - Rio Sollway
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