BMW E30 1990 strange engine poblems...

Hi,
my BMW e30 316 from 1990 has a strange problem: when changing gear and giving it about half throttle, the engine sometimes stalls for a very short time (about a tenth of a second). It is so bad it
feels as if the pistons got stuck. Apart form taht the engine is fine, does not use up any oil and starts very quickly. Then its back to normal. This does not occur if I give it full throttle. Does anyone have any idea what could cause this?
Thanks, Bastian.
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Possibly a vacuum leak. Slim chance it's low fuel pressure. Not a problem I've heard of before.
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Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
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John Burns wrote:

Really? Sounds more ignition / electric control to me since the duration is so short. Ina ny case, certainly not enough info to diagnose it remotely
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I thought about a fuel pump bad relay. But I'd expect that to happen more often than he describes.
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Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
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Auto or manual?
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Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
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It sounds like you may have an intermittent connection in the ignition circuit. My 318i developed a very severe 'bucking' stall like this when my distributor wore to the point that it would whirl in the housing at high rpms and the ignition would stop working abruptly. It could be that the torque of half throttle is moving your engine just enough to cause the wiring to the distributor to short or open. Your car is old enough that some wiring may have worn through it's insulation or broken from fatigue.

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Water in the tank ? I had problems with a carb. Dunno with an injection.

does
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