Immediate Assistance Required: C220d 2016 Experiencing Turbo Boost Insufficiency

[Matt865]

Error code: P029900 (Low boost pressure in Turbo 1) The P228100 code indicates a leak occurring between the Mass Air Flow (MAF) sensor and the throttle. The turbo waste gate of P22C872 is stuck in the open position and is not closing.

On the first day, when I was driving, I observed a consistent rattling sound along with a decrease in power during acceleration, which was then followed by a restoration of power at higher RPMs. Over time, attaining high revolutions per minute (RPMs) became progressively more challenging, and the act of manually changing to a lower gear was no longer feasible. After coming to a halt, I identified the origin of the rattling sound as the left side of the engine (specifically, the turbo), while the engine itself was operating nicely. The OBD diagnostics detected fault codes associated with problems in the intake and turbo valves, namely the waste gate. 1. Identified a pressure leak between the throttle valve and MAF (Mass Air Flow) sensor. The turbo valve is jammed. Despite resetting the error codes, the issue continued, with intermittent fluctuations in boost, ranging from normal to completely missing. While operating a vehicle, I saw the data flow of the waste gate opening, which consistently stayed at about 50% independent of the throttle input (5% when the engine is not running).

On the second day, I had turbo lag at high RPMs. This means that there was a delay in the engine's response after I released the throttle pedal, with the engine still receiving throttle input for 0.5 seconds. Alarmed, I applied a rapid increase in throttle while not moving, resulting in the engine accelerating without restraint. I had to deactivate the engine by extracting the key. Nevertheless, successive attempts to initiate the engine were unsuccessful at first, since the starter was operational but the engine refused to start. After around 10 tries, the engine successfully ignited but released blue smoke from the exhaust. The throttle input at low levels was within the expected range, but, as the engine reached 3,000 revolutions per minute, it suddenly and unexpectedly accelerated without any control. Despite the removal of the key, the engine persisted in running at maximum capacity for around 5 seconds before coming to a halt. I am now apprehensive about making another effort.

At first, I had a suspicion that a waste gate was jammed, resulting in a loss of turbo pressure. Nevertheless, the appearance of substantial blue smoke and unmanageable engine RPMs has caused me great concern.

Has anybody had such situations previously?

Thank you.

 

[bvlenci]

The majority of contemporary diesel engines are equipped with variable vane turbochargers and lack a waste gate.

The presence of smoke and an increase in engine speed indicate a potential failure of the Turbocharger seal, which may be causing the ingestion and combustion of oil.

[Matt865]

I appreciate your response. Following a second instance of the automobile running away, it is now unable to start. When trying to start, the screen becomes black, most likely because there is not enough electricity. Additionally, the starting motor has difficulty rotating the engine, causing it to spin slowly and in an uneven manner. This seems to be an unfavourable indication. Upon inspecting the oil dipstick, I saw that the oil level remains unchanged, and there are no discernible traces of metallic debris. Upon removing the oil cap, there was no visible signs of damage or deterioration. Is it possible for a runaway to cause engine damage? Does a broken turbo oil seal need a turbo repair or a full turbo replacement? Appreciation is extended.

[bvlenci]

Uncertain about the reason why the battery may no longer possess an adequate amount of charge? Were there any battery warning indicators prior to this?

An engine that is out of control may result in significant destruction, however the extent of the damage may be limited if the length of the incident is relatively brief. It is possible that the issue was caused by a malfunctioning fuel injector that was stuck in the open position, resulting in an excessive flow of gasoline.

Turbochargers have the ability to be reconstructed, whereas exchange units refer to turbochargers that have already been reconstructed. At the very least, they should be equipped with new seals and bearings.

Regardless of the nature of the issue, it requires recovery for the purpose of research.

[CodeCrusader]

If the turbo malfunctions and causes the engine oil to replace the fuel, the smoke will become dense like fog. This occurs due to a failure in the turbo seal, which allows the engine oil to be drawn up through the intercooler. To confirm this issue, you can disconnect the lower pipe of the intercooler and observe any substance that comes out. The intercooler pipe will already have some oil residue due to the engine breather, but if a significant amount of oil pours out, it indicates a problem wi If the battery drop has been prolonged, the difficulty in starting the engine might be due to a partial seizure. Do not attempt to operate it until it has been inspected.

[WiseSage]

"A manual transmission can be stalled, whereas automatic transmissions will continue operating until a failure occurs."

What is the procedure for halting a vehicle that is out of control in an automatic gearbox?

[bvlenci]

Obstruct the air intake.

[ForumGuru]

If this vehicle is equipped with two turbochargers, it will have a wastegate.
Indeed, the phenomenon of runaway in an engine may be likened to the situation where the engine continues to consume and burn oil even after it has been shut off.

[CodeCrusader]

I completely agree. You are not relying on gasoline and there is no automatic power shutdown. In the moment of urgency after the first fear and a state of confusion about what to do, you must consider the most effective way to reach the intake. If you happen to have a sufficiently big piece of cloth to totally obstruct it, the shutdown process should begin. However, it is likely that by the time you reach this stage, the situation will have already escalated beyond control. With a manual gearbox, it is possible to stall the engine as soon as the situation becomes uncontrollable, so preventing damage to the engine. I have successfully changed a turbocharger on a second-generation Octavia that operates on oil, resulting in oil leakage throughout the engine. Fortunately, the driver shown prudence by stalling the vehicle via vigorous clutch manipulation.

Edited April 9 by CodeCrusader

[Matt865]

Thank you for your focus. Next week, I will transport the automobile to the garage. Considering that the engine abruptly stopped functioning on its own within a short period of time during both incidents, I am questioning if the engine really had a seizure. Due to the absence of a charging mechanism, I attempted to start the engine today using a depleted battery in order to ascertain whether the crankshaft would rotate. I saw the belt rotating around 45 degrees with each ignition, followed by a halt, indicating that it is not jammed. If the belt is able to spin, would this imply that the engine is not seized?

[bvlenci]

Without a thorough examination, it is only conjecture. Hopefully, it will not result in a disastrous collapse.

Please provide us with the findings of the inspection. 👍

[Motoman]

Typically, the electronic control unit (ECU) instructs the throttle to shut when it detects an overspeed. There is no longer a need to forcefully insert a cloth into the air intake.

[Matt865]

This elucidates the reason for the automatic shutdown of the engine in both incidents. Thank you.

[bvlenci]

I always believed that Diesel engines lack a throttle.

[Motoman]

They possess a throttle, albeit its use differs significantly from that of a petrol engine.

Indeed, during regular operation of a Diesel engine, the throttle is completely open, and the speed is regulated by the amount of fuel being supplied. However, the throttle serves additional functions as well:

The flow of EGR depends on the difference in pressure between the exhaust and intake systems. When the engine is not running at high speed, the difference in pressure between the intake and the surrounding environment may be too low. To address this, the throttle may be partly closed in order to produce a negative pressure in the intake. This results in a larger difference, enabling the appropriate flow of exhaust gas recirculation (EGR).

During the process of engine shutdown, the engine is closed and then opened again immediately after it comes to a stop. This results in a seamless and stable halt without any tremors.

If an engine has an overspeed, the throttle is promptly closed, therefore limiting the amount of air entering the engine. In the absence of air, there is no combustion.

Intentionally reducing the volumetric efficiency of the engine might be beneficial when doing a static regen and aiming to raise heat.

While Mercedes may not be suitable for all these instances, there are other manufacturers who do provide vehicles that are suitable.