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E30 (1982 - 1993)
God's Chariot. The E30 was produced primarily from 1982 through 1991. The cabriolet was the one exception which was produced through 1993.

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Old 01-17-2013, 10:36 AM
alptrans alptrans is offline
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Location: quincy, ca
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Mein Auto: 1984 318i
Power cutting out, idle erratic.

I have an '84 318i that has been starting adequately when cold, but is suddenly subject to wild idle fluctuations and a jumping tachometer with in and out power loss while on the road. this appeared during the afternoon commute for about 3 miles in the middle of a 100 mile drive yesterday, stopped and came back near the end of the drive. the rotor, and cap were replaced since the rotor contact had broken off, and there is some slack in the distributor shaft.
This is a high mileage engine, and there has been a shoosing rattle like overone near the bell housing with blow by on the pistons that is apparent when I pull the valve cover cap. This sound now comes in when the idle and running rpms fluctuate. For the first minutes of curbside warm up it's okay, so I'm hoping it is not a cam to dist. gear problem, or bearing issue. Oil consumption had been normal, but I did have to add to the sump yesterday. Does anyone have suggestions or information about this?

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Old 01-17-2013, 12:04 PM
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hornhospital hornhospital is offline
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Welcome to the fest!

What's the mileage?

The swooshing sound may be an exhaust gasket failing. It's very doubtful you could hear blow-by through the valve cover.

Look for vacuum leaks. The description of you removing the oil filler cap and the car continued to run poorly but run tells me it already has a substantial vacuum leak somewhere. Normally when you remove the cap the idle will go to crap. BMW engines hate three things: vacuum leaks, low fuel pressure, and overheating. Sounds like you have the first one.
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Old 01-17-2013, 02:54 PM
alptrans alptrans is offline
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Location: quincy, ca
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Mein Auto: 1984 318i
Thanks for the reply. I checked the vacumn hoses, and taped over some cracks on the link between the idle control, and the intake manifold. The hoses to the vacumn connection on the firewall and back to the intake manifold and vacumn advance look okay. The things stills runs but I come to town on the back road and gently ease the throttle along to avoid the quick rpm increase that comes before the short cut outs.
The head pipe gasket was replaced recently, I don't know about the exhaust manifold gasket. I see from the Bentley 3 shop manual that the distributor shaft slack could be the problem. The replacement rotor lost its contact inside of a day and the shaft can be moved a sixteenth of an inch plus. according to the manual the result might be a variance from the pulse generator, and so the problem. If I pull the leads to the idle stabilizer the engine accelerates like mad. Thanks again.
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Old 01-17-2013, 06:18 PM
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BMWFatherFigure BMWFatherFigure is offline
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Mein Auto: E23;E32;E34;E38;R50;R55
Wear in the dist shaft can contribute to cap/rotor damage. There is not much clearance and they will hit if free movement is present. Get brave, fit that and replace the obscenely expensive air inlet hoses. Tape is never a good fix - sorry. Look at it this way - $70 part has lasted since 1984 - it is just you are the unlucky bastard it failed on.
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Old 01-18-2013, 07:46 AM
alptrans alptrans is offline
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Location: quincy, ca
Join Date: Jan 2013
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Mein Auto: 1984 318i
Thanks for the heads up Bmwfatherfigure. I had a good look see at all of the inlet hoses, and yes it is time. The distributor adds up as the problem since the vehicle still operates, except when a quick increase in the rpms leads to the engine cutting out; shifting from fourth to fifth and back at lower rpms avoids that..for the moment. Am out on the hunt for the replacement. Thanks Hornhospital for the mention of the exhaust gasket also. It's been cold enough here that I'd want to lose any leak there soon, never mind I hadn't thought of this until you mentioned it. The help is much appreciated.

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