Omega Owners Forum
Chat Area => General Car Chat => Topic started by: JamesV6CDX on 27 March 2016, 15:52:11
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My 530d e39 3 litre turbo diesel
Last week, massive power loss, big hiss of air under acceleration, loads of black smoke from exhaust
Found a 2 inch split in a turbo pipe between turbo and intercooler. Result thinks I.
All boost pipes very soft so I replaced them all with brand new ones
Week later. Noticed a (lesser) hiss under accelerating today.
The same pipe has split again!!!
It must be under a massive amount of excess pressure to be doing this to a new pipe!
Any ideas? Why would it over boost that much? I want to fix it but time isn't on my side, I need a reliable car for my commute.
I have access to the software to read codes and live data
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Boost pressure?
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Boost pressure?
Definitely seems it's the boost pressure too high, but I know very little about what this could be or how to diagnose it
There are similar issues on forums but no actual resolutions
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Does it have a dump valve, either to air or recirculating?
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Mechanical or electrically controlled turbo on these?
Has someone "fiddled" with the wastegate linkage?
Is the linkage seized in the open position?
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Vacuum controlled I believe
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Boost pressure?
Definitely seems it's the boost pressure too high, but I know very little about what this could be or how to diagnose it
There are similar issues on forums but no actual resolutions
What is it reading?
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Will need to check :y
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sound like blocked cat to me
air pipe did you replaced with new or used?
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sound like blocked cat to me
air pipe did you replaced with new or used?
Thanks Serek :y
Any easy way to test the cat?
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New pipes :y
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Does it have swearl flaps, any chance they can be stuck closed? I know they are a problem on bmws
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Internals of the Intercooler collapsed and causing a blockage? Quite common on the Saabs, pressure builds and builds until it lets go with a woosh!
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Does the turbo have variable vanes to control the boost pressure?
My only diesel experience so far is of our 1.9tdi galaxy. When the vanes in the turbo started to seize we had intermittent limp mode due to excess boost.
Getting the turbo off and freeing the vanes was tedious but not too difficult and seems to have solved the problem for now. Galaxy has done 140,000 miles.
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I'd have thought the ECU would have shut it down before the boost got high enough to fracture ducting, unless someone has been playing with the mapping. ::)
Could well be a blockage between turbo and MAP sensor though. Need some live data from it, really
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What values would be most useful Kevin? :y
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I'd have thought the ECU would have shut it down before the boost got high enough to fracture ducting, unless someone has been playing with the mapping. ::)
Could well be a blockage between turbo and MAP sensor though. Need some live data from it, really
I wonder where the MAP sensor is located :-\ if it is after the intercooler that could point to a blockage in the intercooler.
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I'd have thought the ECU would have shut it down before the boost got high enough to fracture ducting, unless someone has been playing with the mapping. ::)
Could well be a blockage between turbo and MAP sensor though. Need some live data from it, really
I wonder where the MAP sensor is located :-\ if it is after the intercooler that could point to a blockage in the intercooler.
in intake manifold at back of engine
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It's worth cleaning the manifold pressure sensor and ports
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The only fault code is "boost pressure too big"
Looking on live data the charge pressure with the engine at idle is 1000mbar
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1bar over atmospheric at idle would be impressive so that suggests it's an absolute reading; 1bar being standard atmospheric pressure i.e. 0 boost..
What about when you're (significantly) off idle and under load?
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I think "boost pressure too big" and a penchant for splitting the intake ducting tells us something.
Depends how the boost pressure is controlled on this engine, but something's clearly amiss in the control system. It would be good to see how the boost pressure behaves under load, indeed.
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There are apparently two "pressure control valves". If It would stop raining I'd be able to have a look!
Annoyingly my cable isn't long enough for live data, the diag port is under the bonnet!
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I'll be down your way this weekend, so I can help you out.
I'll razz along in the car while you sit on the bonnet with your laptop. :)
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There are apparently two "pressure control valves". If It would stop raining I'd be able to have a look!
Annoyingly my cable isn't long enough for live data, the diag port is under the bonnet!
Jesus, how old is it :o
Regulations for last 15years have been it must be in cabin, within 1m of steering wheel.
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There are apparently two "pressure control valves". If It would stop raining I'd be able to have a look!
Annoyingly my cable isn't long enough for live data, the diag port is under the bonnet!
Jesus, how old is it :o
Regulations for last 15years have been it must be in cabin, within 1m of steering wheel.
The BMW E39 is the fourth generation of BMW 5 Series, which was sold from 1995 to 2004
Somewhere in that range ;) I'm guessing it's the earliest round diag port (looks rather like a small trailer socket) under the bonnet, before they moved to OBD ports in the cabin, late 90s..
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Technically the scuttle is within a meter of the wheel ;D
No point having rules if you cannot interpret them to suit... ::)
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Technically the scuttle is within a meter of the wheel ;D
No point having rules if you cannot interpret them to suit... ::)
:y
Manifold off. Noticed a few things, will update later :y
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There are apparently two "pressure control valves". If It would stop raining I'd be able to have a look!
Annoyingly my cable isn't long enough for live data, the diag port is under the bonnet!
Jesus, how old is it :o
Regulations for last 15years have been it must be in cabin, within 1m of steering wheel.
Some Beemers circa 2000-1 have both types of diag plugs,16 pin under dash,old BMW round plug under bonnet ::)
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Having taken the inlet manifold off ALL the vacuum hoses are perished to nothing. I believe they are collapsing internally under any sort of pressure. So all vacuum hoses will be changed.
I cannot work out if there is a Very small trace of metal filings in the inlet ports on the head !
There are none I can see in the boost pipes.
EGR is coked up badly. Have ordered a replacement EGR blanking kit
Swirl flaps are all present but have ordered a blanking kit
When removing the manifold one of the rubber backup washers with a metal ring is unaccounted for. Can't find it anywhere. Am worried it's fallen into an inlet port on the head.
I've ordered a bore scope. It may just be in a nook or cranny or maybe was never there. But I don't want to wreck the engine!
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Oh the manifold itself, map sensor and port were coked up
Replace, or, clean?
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Apparently a soak in caustic soda overnight does wonders for the intake manifold. Not tried it myself and be careful with any aluminium parts.
If you can clean the map sensor (very carefully) then why not. Just use diagnostics (INPA would be fine) to check it's reading correctly.