random high idle

1996 BMW 318I
153,000 MILES • 4 CYL • 2WD • MANUAL
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PROILLUSTRATOR
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Engine has recently begun fluctuating its idle, when the engine is cool the idle stays just below the 1 on the RPM guage, as the engine becomes hot when in the lower gears the idle either revs up to 2 on the RPM guage and hangs or returns back to the below 1. it can get stuck in the high idle or it will rise and fall randomly.


Attempts to resolve include:

replaced the spark plugs with correct manufacturers recommended brand

Replaced the oil with manufacturers recommended 5W-30

replaced oil filter

replaced fuel filter

removed part that comes off the air filter and cleaned it with carberator cleaner as recommended let it dry over night before reassembly

I regularly check oil and coolent levels

what exactly am I missing that will resolve this issue?
Jun 14, 2011 at 8:29 AM
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RASMATAZ
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Inspect and test the idle speed control valve and MAF sensor
Jun 14, 2011 at 8:36 AM
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PROILLUSTRATOR
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I have replaced the idle speed control valve. Is there a way to clean it without damaging it? what kind of cleaner do I need for the MAF sensor?
Jun 14, 2011 at 10:48 AM
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RASMATAZ
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For the MAF sensor use an electronic cleaner CRC
Jun 14, 2011 at 2:24 PM
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PROILLUSTRATOR
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Ok I cleaned the MAF and the idle speed control valve with the recommended product my engine is now experiencing a rough quake in the idle at low speeds and my service idicator lights haven't gone out?
Jun 21, 2011 at 12:26 PM
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DOCHAGERTY
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OK, the Dr. is in, give me the last 7 of the VIN so I can ID the car and zero in on the solution.
Jun 25, 2011 at 2:41 AM
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PROILLUSTRATOR
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JF24368 I am now experiencing the stalling again. it seems to happen mostly once the egine has gotten warm. Sometimes it will start if i put it in 1st and hold down the clutch at other times I have to adjust the throttle other times just have to sit and wait. I am just guessing now but when my tank is above half the engine performs normal but under half a tank and I end up having to make adjustments to get it started. This is going on 5 months of trouble shootomg I starting to lose my patience and tolerance for BMW's. Help
Jun 27, 2011 at 1:31 PM
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DOCHAGERTY
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Check/replace the crankcase vent valve, PN: 11157501567
Jun 28, 2011 at 12:35 AM
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PROILLUSTRATOR
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Crankcase vent valve replaced with a brand new one. Was running fine then once again once the engine was warm started fine but when i went to engage the excellerator the engine starting dieing I had to press down quickly a few times before the engine wanted to act right again.
Jul 11, 2011 at 7:30 AM
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DOCHAGERTY
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Any fault codes?
Jul 15, 2011 at 10:38 AM
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PROILLUSTRATOR
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it says inspection and is still showing in the yellow and red codes. I get the sense its gasping for air somewhere, it will sound clear no noises then if it does the trouble start thing, its sounds like its muzzled not severely but enough to feel it in the exellerator and a ticking noise becomes previllant in the lower rpm's.
Jul 17, 2011 at 6:18 AM
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DOCHAGERTY
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Are there any currently present fault codes?
Jul 22, 2011 at 4:46 PM
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PROILLUSTRATOR
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Only inspection
Jul 25, 2011 at 9:27 AM
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PROAUTOTECH
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Check all the small rubber vacuum lines. They get brittle and get tiny holes in them. Bad lines will easily do this. Vacuum lines are cheap, you can buy it buy the foot. If you can't see anything brittle, you can spray them down carefully and slowly with carc cleaner or staarting fluid. The rpm will change if it has a leak. You want to stay away from the spark plugs and wires though, if you have a misfire (spark). You can catch your engine on fire. Or just go and replace all of them now, your car is almost 15 years old, it's time. If that doesn't help, use the spray method around the intake maniflod and throttle body. I'm strongly thinking air leak.
Oct 2, 2011 at 11:02 AM
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99RAM4X4
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Idle air controller. Within air intake system.
Jan 25, 2013 at 4:46 AM