BMW 420d MSport engine power loss when hot

BMW 420d MSport engine power loss when hot

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Griff65

Original Poster:

6 posts

69 months

Thursday 19th July 2018
quotequote all
Hi All

I have a 2015 420d MSport (20K on clock) and had after warranty service some 3 months ago.

On a long run some 6 weeks ago, the engine started "stalling" and losing power. This only happened after a good hour on motorway driving. On way home, it started playing up again... No engine management lights on...

I took to local garage and explained that some 2 months ago, I inadvertently run fuel down to min (no garages nearby). Most of my driving is local. So he suggested filling with high octane diesel and add DP Filter cleaner and give it a long run at over 3,000rpm.
I did this and all seemed fine until after about 30mins, when it again starting losing power (almost like a fast stall, but losing power, juddering). It does this for about 10 secs, then all is ok. But comes back periodically...

Two days later (fuel level down to 1/2 tank), I tried it again... And same... all fine until after about 25mins fast driving (3,000rpm) and then bursts of loss of power again.

I have heard may be the DP Filter but would have thought I would have regenned it on fast run, car only has 20K on clock, no engine management warning lights on.

I'm at a loss here as to what could be the cause. Any help, suggestions would be much appreciated

Cheers
Griff

Griff65

Original Poster:

6 posts

69 months

Thursday 19th July 2018
quotequote all
Hi E-bmw

Many thanks for the quick reply and advise. I changed my job 2 yrs ago which meant I could work lot closer to home - the only run the car gets now is to the shop or to/from airport once a month.

I'll try the DPF clean and see if that is the problem. I dont have any engine warning lights on, so got me thinking perhaps a fuel issue?

Anyway, I'll give it a go and let you know.

Cheers
Griff

Griff65

Original Poster:

6 posts

69 months

Saturday 21st July 2018
quotequote all
Thanks all for your advice. I've booked it in for next Thursday. Let you know if they find anything and hopefully may help someone who sees similar issue

Cheers
Griff

Griff65

Original Poster:

6 posts

69 months

Sunday 19th August 2018
quotequote all
Update,,,
Took to garage - DP Filter was fine, but there was a fault code pointing to the camshaft position sensor.
So having replaced it, they found out that that one was defective....
Anyway, new one fitted and was fine with 2 hr drive to airport, 2 hrs back... Fixed?... wrong..

Today after a run of about an hour, started again to get power loss and stuttering...

Any ideas?

Regs
Griff

Griff65

Original Poster:

6 posts

69 months

Monday 15th October 2018
quotequote all
Resolved!

It was the crankshaft sensor. My local garage said that they had already fitted 2, and again showing same issue on the magic box and so had to go back to BMW . BMW fitted another and have had no problems at all since (No charge).

Word on the grapevine is that BMW had received a dodgy batch and were keeping it quiet. When I asked BMW they said categorically no issue with crankshaft sensors...

So if you get same sympton, it could be the this!

Cheers all for your suggestions

Regs
Griff

Griff65

Original Poster:

6 posts

69 months

Monday 15th October 2018
quotequote all
Aye, my mechanic said the units he got from BMW were very flimsy and likely when hot, they broke down.
He also rec to use super diesel for DPF as the additives in it are worth the extra money.
So fingers crossed.
Thanks again for all the advice
Cheers
Griff