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Fault code 04390, acceleration hesitation, jerking, and poor performance

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I have just encountered a problem with my E92 320d 2008.

During periods of high engine load (such as strong acceleration, somewhat low RPM in a higher gear, and passing on the motorway) about 2000-3000rpm, the engine exhibits significant jerking motion, resembling the sensation of gasoline being deprived from the engine.

The mpg gauge and rpm were monitored, while the windows were down. The observed symptoms indicate a temporary cessation of fuel supply to the engine, followed by a subsequent resumption.

The problem may persist throughout the day, temporarily subside for a duration of 30 minutes, and often manifest while the engine is in a heated state.

When operating a vehicle in an elderly manner, the vehicle performs well. However, when subjected to significant acceleration, the vehicle seems to encounter a stumbling issue, hence reoccurring the problem.

Last week, I changed the MAP sensor, which was the original and had some carbon residue. However, the problem persists.

The encountered error code is 04390, which pertains to the charge air temperature management.

I have erased all codes, observed the automobile, and immediately copied the proved code, which was the only code present.

Do you have any suggestions? Insufficient internet resources. There are differing opinions on whether it is the MAP sensor or the throttle body. However, it may be inferred that the code is perhaps associated with the management of manifold pressure or boost control.

Suggestions? I have not seen any discussion where someone has successfully identified this.

Thank you very much!

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Could you provide me with the precise location?

I will examine tomorrow.

In relation to the DPF, I commute around 60 miles every day on the motorway and experience a substantial 30-minute acceleration either on my way home or to work, which has led me to disregard the DPF concerns. Typically, do you get a signal or light indicating that the DPF is blocked?

The intermittent occurrence of a modest decrease in power on the motorway, accompanied by the olfactory perception of eggs, in conjunction with a slow throttle response, is perceptible to me.

I am hopeful that the DPF is not the cause, since I perceive it to be rather expensive in the event of an unsuccessful forced regen.

Thank you.

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Apologies, the pipe in your automobile is not made of metal. Here is component number 7. RealOEM.com is an internet-based catalogue of BMW parts.
The DPF regen should not induce any sluggishness, however it may result in a coarser engine tone.
A code of 480a would be assigned for minor blockade, while a code of 481a would be assigned for substantial blockade.

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Thank you for the diagram, it is really helpful.

Despite many attempts, I was unable to determine if it was the MAP or MAF sensor, resulting in a dead end.

I will examine it tomorrow and inform you whether that resolves the issue.

I will also verify whether any recent codes have been activated, since I presume that this malfunction is preventing me from accessing the regen settings, and this issue has been persisting for many weeks

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A scanner is necessary to accurately measure the dpf backpressures. However, it seems that you are experiencing a fueling problem.
It is hypothesised that a malfunction occurred in the injector wiring loom located underneath the intake manifold, resulting in the occurrence of chaffing and earthing out of the wires.

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Your assertion was confirmed. The air temperature sensor was located on the intake. The metallic clasp has disengaged and the housing has become free. Repositioned it to verify its functionality and subjected it to a vigorous use for a duration of one to two days, resulting in its optimal performance once again.

Ordered a new sensor, housing, and clip.

Excellent! Additionally, I own a new MAP sensor as a precautionary measure.

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