Oil light flickers at idle

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320Touring
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Post Sun Jul 03, 2005 8:43 pm

heres one that is puzzling me..

mate has an e34 m20 520i (soon to be mine hopefully :wink: :lol: )

was running really roughly-did the AFM/ICV cleanup and sorted the one air leak we found.

also loosened off the throttle cable so it idled lower.

now sits at 700, only to jump up to 1100 randomly.

moreover-the oil light (the wee oil pot with a drip) flickers on when at idle.

level of oil is good, and no signs of it mixing with water etc...

i really am :mad: :mad: :? over this
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tourer-dan
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Post Sun Jul 03, 2005 9:09 pm

As far as I understand a low oil pressure on idle is not the end of the world. The oil pressure increases with engine speed, so it will be high enough to be safe when the revs pick up as ther light goes off. If the light stays on (or comes on) when you're driving it is much more serious. If you are worried, have the oil pressure tested by a garage. A low pressure could either be a worn pump, or a worn engine. If it was anything more serious you would have known about it by now.

Having said that if my oil light did this I personally would want to rectify the problem.
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stevo
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Post Sun Jul 03, 2005 9:52 pm

i've got this prob too, my mechanic mate says an oil change with thicker oil should help, which ive not done yet. its just because of the high mileage and nothing to worry about :wink:
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Post Sun Jul 03, 2005 9:54 pm

stevo wrote:i've got this prob too, my mechanic mate says an oil change with thicker oil should help, which ive not done yet. its just because of the high mileage and nothing to worry about :wink:
what mileae has your car got? the 520i has 123k on it
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stevo
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Post Sun Jul 03, 2005 9:55 pm

just over 155k
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Post Sun Jul 03, 2005 9:57 pm

stevo wrote:just over 155k
cool may just dod thicker oil in and try another ICV :cool: :cool:

thanks for putting my mind at ease fellas :D
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Post Sun Jul 03, 2005 10:12 pm

i suggest changing ure oil press sensor/switch and then seeing..... before u jump to conclusions bout low oil press...

Karan
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Post Sun Jul 03, 2005 10:14 pm

mines got 192 and runnin semi
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Sooty
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Post Sun Jul 03, 2005 11:56 pm

I was going to advice checking the oil pump gear but then I noticed this is for the M20 engine & not the M50. :oops:
:stupid:

BTW...putting thicker oil in is a bodge artists trick just before selling the car on to some poor unsuspecting mug.
No real mechanic would ever suggest this & I would seriously avoid any clown that did.
Last edited by Sooty on Mon Jul 04, 2005 12:06 am, edited 1 time in total.
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Brianmoooore
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Post Mon Jul 04, 2005 12:04 am

stevo wrote:i've got this prob too, my mechanic mate says an oil change with thicker oil should help, which ive not done yet. its just because of the high mileage and nothing to worry about :wink:
I suggest you find a new mechanic - one that knows something about engines.
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Post Mon Jul 04, 2005 12:09 am

justchange the oil pressure switch first
you will prob find the light willgo out instantly
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Martinaston
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Post Mon Jul 04, 2005 12:17 am

Are you sure it's not just a loose connection that shows up at that specific vibration ?
Get someone to push on the plug when it's ticking over and have a look.
320Touring
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Post Mon Jul 04, 2005 1:57 pm

Martinaston wrote:Are you sure it's not just a loose connection that shows up at that specific vibration ?
Get someone to push on the plug when it's ticking over and have a look.
I'll do that mate-the oil sender was the only other thing i coul think of...

thanks everyone!!!!! :cool:
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sabrje
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Post Mon Jul 04, 2005 4:54 pm

Mine was doing the same - turns out it was the wire that goes around the front of the engine from the pressure switch rubbing on the alternator belt....

Worth checking!
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Post Mon Jul 04, 2005 7:11 pm

mine used to come on whenever i crossed 120, (most days then!)
the wire was blowin back on to the exhaust manifold and gettin an earth off it!
got a wicked shock when it first happened