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Discussion Starter #1
Oil pressure warning came on for a few seconds and then went away.

When I start the car and leave it on idle there is a metallic noise coming from the front of the engine, kind of like when cogs are are missing on a chain.

Now I know this is probably (he says) my timing chain tensioner shagged but why the low oil pressure?
 

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Cyrus said:
Oil pressure warning came on for a few seconds and then went away.

When I start the car and leave it on idle there is a metallic noise coming from the front of the engine, kind of like when cogs are are missing on a chain.

Now I know this is probably (he says) my timing chain tensioner shagged but why the low oil pressure?
I think the timing chain drives the oil pump and would avoid starting her till the tensioner is replaced then check her out. I could be wrong old bean. All others welcome to add their 2 cents...............

Hope it`s not terminal mate :byee55amg
 

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Discussion Starter #3
How hard it is to change the tensioner on a 3.6?
 

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A breeze apparently just undo the nut and swap with new one,i think the e36 m3 tensioner is a better replacement but check old threads to see for sure

good luck :byebye:
 

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Discussion Starter #5
And this should cure the problem?

So whats happening is that the old tensioner has gone slack hence the timing chain has gone slack which in turn isnt turning the oil pump enough bringing down the oil pressure?

If this is the case its a **** good thing I just stopped driving it!

Better go and get tensioer tommorrow.
 

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Cyrus said:
And this should cure the problem?

So whats happening is that the old tensioner has gone slack hence the timing chain has gone slack which in turn isnt turning the oil pump enough bringing down the oil pressure?

If this is the case its a **** good thing I just stopped driving it!

Better go and get tensioer tommorrow.
The timing chain doesn't drive the oilpump, it is driven by a seperate small chain located behind the timingchain. The timingchain goes up from the crankshaft, the oilpumpchain goes down. The only thing they share is the sprocket on which they run, a sprocket with 3 rows of teeth kept on time with a keg, mounted on the crank by the central bolt. Even if the tensioner has fallen apart, which I doubt, the hole in the side of it's housing which lets in the oil in is so small it could never cause a lack of oil-pressure. Not having replaced it for the improved (risk-free) version is something I cannot understand, but is your decision.

From reading your post the only conclusion I can come to is that something momentarily blocked the oil-pump, and is rattling inside or under the pump now. That momentary drop COULD cause the tensioner to release, but proper pressure should reinstate it. If oilpressure is still not up to spec something is in there. Might be 1 demolished chamber it the pump you're hearing. Drop the front sump and find out. Also pull the oilfilter and inspect it. I know the S38 doesn't drop loose bolts in the sump as the V8's are famous for, but I've had my share of bit's flying around the sump..... Caught them before they could hurt me. Pictures on the link are not from one, but TWO 540i's we pulled apart on the same evening.

http://www.m5board.com/vbulletin/showthread.php?t=54990

Good luck, I hope she'll survive!
 

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Hi!
Well, theoretically its possible that if the tensioner has failed , the timing is off by so much that the idle isn`t high enough to maintain oil pressure. The sound you describe sounds like the one I experienced ca. 6500eur ago.
DON`T START THE CAR AGAIN!!! Change the tensioner and see if the sound disappears, and then measure your oilpressure/drop the sump to check oilpump.

Hope it sorts out cheaply
Sakke
 

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Discussion Starter #8
I spoke to Bexley Motor works today and it doesnt sound very promising.

They too confirmed that the oil pump is driven seperately. The noise Im hearing is coming from the front of the engine, not something inside.

Oil pressure only drops at idle. It may well be something inside, will open a few things up and check whats going on.

Thanks for your replies but i am truly depressed at the thought of what this could cost.
 

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Apologies for the bad info on the chain. Just remember when i replaced the oil pump(memory obviously not as good as i thought)it was connected down there forgot the separate chain ouich

Hope you get her sorted :wroom:
 

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Discussion Starter #10
Had it checked out today at bexleys, the weird noise is the air pump clutch knackered.

The oil pressure is fine, it was most definately an electrical fault of some sort.

Im going to take off the sump anyway and see whats going on and if anyone has any tips of preventitive maintenance that would be great.

Chain tensioner is something going to do in the next few days anyway.
 
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