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stevepoulter

Engine Fault Reduced Powrr

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Hi all,

 

I wonder if you can help me.

 

I own a 2010, BMW F10 520d AUTO with approx 74k on the clock.

 

I have had the car for 6 years and it has been perfect with ZERO problems, however (the reason I am here) since Saturday (16/09/2017) the vehicle is not well.

 

I am getting

 

"Engine Fault Reduced Power"

 

Flash up on the instrument cluster, this fault flashes up intermittently every few minutes. When it comes up the engine looses power. After about 10 seconds the fault disappears and engine power is restored. For example on a 5 minute journey this cycle can happen 5/6 times - as you can imagine the car is undrivable.

 

Sometimes during driving the Dynamic Stability Control fails and i get the error;

 

"Dynamic Stability Control Failure"

 

This is not too often and once this comes up it does not disappear unless I turn off the ignition and restart the car - then it has gone.

 

Recent Work:

 

The last work on the car was an OIL CHANGE approx 5 months ago I took it to MBM Autohaus in Birmingham who are usually very good but they guy who did the oil change didn't have a clue. When I got the car back the error message (Engine Oil Level Too High) came up once I got home, I checked the dipstick and the oil level was on the maximum marker, not higher and this error disappeared after a few hours. They also didnt know how to reset the Oil Service light and I had to You Tube and do this myself.

 

Thats the only recent work done.

 

I took the car today to a friend who owns a Snap On diagnosis machine and I got an ECU error fault as well as a whole host of others, I have got screenshots added below

 

 

If you need any more information please don't hesitate to ask.

 

I have opened the ECU case, checked cleaned all connections

 

I have checked every single fuse. All OK

 

I have checked the battery and alternator. All OK

 

I have checked every single wiring connection I can get my hands on and cleaned. All OK.

 

Please help586a0e36841e837194c9d63ce2c396d3.jpg1243b43733bf85cd9c3a985080011ced.jpg

 

Sent from my Nexus 6 using Tapatalk

 

 

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Similar problems have been on here before and the 2 most common causes were

1. a build up of water by the engine ecu caused by leaves blocking the drain holes.

2. the battery beginning to fail.

 

 

 

Sent from my iPhone using Tapatalk

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Thanks guys. Can water get into the ECU case? I thought it was completely sealed

 

I took the lid off and the top was dry but I didn't check the bottom by removing the ECU. I will completely remove the ECU tomorrow and check.

 

I will also check for blockages, I have two huge trees right over my car and I always have leaves all over the car and the sticky SAP stuff. It's a nightmare.

 

I am presuming if it is water damage, the drying out process should restore a proper circuit.

 

Thanks again

 

Sent from my Nexus 6 using Tapatalk

 

 

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49 minutes ago, stevepoulter said:

Thanks guys. Can water get into the ECU case? I thought it was completely sealed

 

I took the lid off and the top was dry but I didn't check the bottom by removing the ECU. I will completely remove the ECU tomorrow and check.

 

I will also check for blockages, I have two huge trees right over my car and I always have leaves all over the car and the sticky SAP stuff. It's a nightmare.

 

I am presuming if it is water damage, the drying out process should restore a proper circuit.

 

Thanks again

 

Sent from my Nexus 6 using Tapatalk

 

 

 

The Snapon reader, while it is showing you faults, it isn't showing the mileage at which the fault happened. With ISTA and an ENET cable you'd be able to read the codes and see when they occurred on the same screen. I suggest you take a full printout of the errors and then clear all faults and start again to see which ones come up first. Leaf contamination is never a good thing with these cars (and others I'm sure) and now I am overly conscious of any leaves dropping on the car and remove them as best as I can before driving off.

 

If the ECU did become water damaged there is a high possibility that simply drying it out won't resolve the issue as shorting may have happened and taken out components on the board. I assume you've taken a look at this thread: where due to leaf and water build up a relay had failed?

These are very difficult things to diagnose but you are looking in the right areas. Also be cautious about driving the car in its current state as the fault could have a knock on impact elsewhere in the system.

 

Where are you based, I have ISTA and the cable and would be happy to take a look - I'm near Bromley in Kent.

 

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Thanks for the reply.

 

I am in Birmingham unfortunately.

 

I did clear all the codes after taking the screenshots and they all reappeared as soon as I took the car for a drive.

 

I will be looking at the leaf clogging areas later to make sure there is not water build up.

 

 

 

Sent from my Nexus 6 using Tapatalk

 

 

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Hi Steve, 

 

I had the same error pop up about 4 weeks ago now. Mine happened after the car was low on fuel and re-filled. Since then the cars been flawless again. My faults were cleared with Carly and not returned......Fingers crossed.

 

 

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Hi Steve, 

 

I had the same error pop up about 4 weeks ago now. Mine happened after the car was low on fuel and re-filled. Since then the cars been flawless again. My faults were cleared with Carly and not returned......Fingers crossed.

 

 

I hope it's an easy fix. It's hard work walking the children to school, 50min round trip!

 

Does anyone know where this DDE relay is located ? I can't seem to find it anywhere online.

 

I'm going to clean out all the leaves today. The fuel has never been too low and currently I have half a tank in there.

 

Thank again guys, I'm sure we'll get the the bottom of this

 

Sent from my Nexus 6 using Tapatalk

 

 

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18 minutes ago, roundy said:

Hi Steve, 

 

I had the same error pop up about 4 weeks ago now. Mine happened after the car was low on fuel and re-filled. Since then the cars been flawless again. My faults were cleared with Carly and not returned......Fingers crossed.

 

 

 

If thats fixed the issue then i would be looking into diagnosing the fuel pumps, low fuel in the tank can cause the pumps to work harder and cause issues. E39 memories coming back to me..... :unsure:

 

when was the fuel filter last changed? its now in a stupid location (under the car near the passenger side sill)

Edited by IINexusII

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Full service was done just under 6 months ago and that was me being abit over the top as it had already been done recently by a Bm specialist. I wanted piece of mind knowing oil had been changed & all the relevant filters etc.

 

Touch wood :) 

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27 minutes ago, stevepoulter said:

I hope it's an easy fix. It's hard work walking the children to school, 50min round trip!

 

Does anyone know where this DDE relay is located ? I can't seem to find it anywhere online.

 

 

 

 

Hi Steve, have a look here, it shows the general area location: http://www.realoem.com/bmw/enUS/showparts?id=FW12-EUR-12_2009_F10_BMW_520d&diagId=61_3754#61368373700

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Hi Steve, have a look here, it shows the general area location: http://www.realoem.com/bmw/enUS/showparts?id=FW12-EUR-12_2009_F10_BMW_520d&diagId=61_3754#61368373700

With that location I can see how water can cause a fault. I had a quick look earlier and there are a shed load of leaves under that grill.

 

 

 

Sent from my Nexus 6 using Tapatalk

 

 

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33 minutes ago, stevepoulter said:

With that location I can see how water can cause a fault. I had a quick look earlier and there are a shed load of leaves under that grill.

 

Sent from my Nexus 6 using Tapatalk

 

And from what I can remember a sod to get those deep in the crevices out!

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And from what I can remember a sod to get those deep in the crevices out!

I've just gone out in the pouring rain to see if I can see water leaking onto the relay housing. There is literally a mini water fall pouring directly onto the relay housing loom and relay housing box.

 

I made a video, this can't be normal. If it is, then this is a serious design flaw....

 

I won't open the relay box up in the rain but I am sure there must be water in it.

 

Sent from my Nexus 6 using Tapatalk

 

 

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There is a massive thread on this Steve, one of the threads is in an attachment Andrew has listed above. Do you have the video to show us?

The video is too large to post, 338kb too big. I've tried to trim it but it's not working.

 

I'll keep working at it and as soon as I worked it out I'll post it

 

Sent from my Nexus 6 using Tapatalk

 

 

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10 minutes ago, stevepoulter said:

The video is too large to post, 338kb too big. I've tried to trim it but it's not working.

 

I'll keep working at it and as soon as I worked it out I'll post it

 

Sent from my Nexus 6 using Tapatalk

 

 

 

As a fellow #AndroidMasterRace Nexus user (looking at your post) you can backup the video to Google Photos and share the link out :)

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3 minutes ago, nashdm2 said:

I can see it but I am struggling to see where hat is in the engine bay?

 

It is being filmed from standing next to the driver side front wheel, side on to the car, the object in the foreground is the bonnet opening hinge/mechanism.

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