Power Loss on Cold Start – F15 X5 M50d

[MSP66]

Dear forum members,

I drive a 2017 BMW F15 X5 M50d with 120,000 km on the clock. I’ve noticed that when starting the car in the morning—or after it’s been parked for several hours—it exhibits a noticeable lack of power and sluggish throttle response. However, if I switch the car off and restart it, the issue disappears and the vehicle drives normally.

I took it to the nearest BMW dealership, but they were unable to pinpoint the root cause. They suspect a valve in the intake manifold may be to blame. However, I find it puzzling that if the valve were indeed faulty, a simple restart would resolve the issue—at least temporarily.

I would appreciate any advice on what might be causing this problem, and recommendations for a workshop that can carry out a more accurate diagnosis.

Thank you

 

[MOE 000 GP]

Blocked cat?

 

[mosome]

Does the car go into limp mode and goes away on restart? I know exactly what the problem is, had similar in mine, now sorted.

 

[MSP66]

Does the car go into limp mode and goes away on restart? I know exactly what the problem is, had similar in mine, now sorted.

Yes, exactly. Would you share how you sorted it?

 

[MSP66]

Blocked cat?

Not sure !

 

[mosome]

Yes, exactly. Would you share how you

Yes, exactly. Would you share how you sorted it?

Please whatsapp me on 0827911479.

 

[msm]

Does the car go into limp mode and goes away on restart? I know exactly what the problem is, had similar in mine, now sorted.

How about sharing what the problem was?

 

[Xcede Performance]

Sounds like a faulty swirl-flap actuator in the intake manifold causing the lever to get stuck intermittently.

Common issue on these. Many have had the manifolds replaced while still under motor-plan.

We do a lot of these in the 40 and 50d variants and solve them by disabling the swirl-flaps via the ecu map.


Sent from my iPhone using Tapatalk

 

[mosome]

How about sharing what the problem was?

In all likelihood it's the swirl flap mechanism. The only fix is either to replace the whole intake manifold (very costly) or repair the mechanical failure. In both cases, the intake manifold will have to be removed.

A software deactivation of swirl flaps will NOT resolve the problem, unfortunately. Once the repair has been done then the software deactivation will work. However, any delete of swirl flaps in a diesel will result in loss of lower down torque and higher fuel consumption. In the M50D the loss of lower down torque is so pronounced and fuel consumption rose by 2L/100km in my case. It was so bad I had to take the car back to stock settings with swirl flaps operating normally.

As I mention in another post, I have carbon cleaned my car last week. The carbon buildup was bad with intake covered in carbon. The car drives much better now with less frequent DPF regeneration (average interval of 700km vs 450km, due to less soot I guess), 0.5 to 1L/100km fuel consumption improvement and quieter running engine.