ASV Error Database: Troubleshooting & Solutions

Hello everyone,

As you probably know, I've been having problems with my VTG (or at least, I think I have).

I just read the error codes from my shop's diagnostic tool, and guess what...

Error: 17965 P1557 035
Boost pressure control.
Limit exceeded.

Okay, so I went into the error database, and under this error, it says:

Error code: 17965.
Boost pressure regulation: Limit exceeded.

Possible causes:
Hoses connected incorrectly, not properly attached, leaking.

and under 'Errors':

Error code: 17964.
Boost pressure control: Limit exceeded.

Possible causes:
Faulty boost pressure control valve (N75), leaky hose connections.
Turbocharger failure.
Air leak between the turbocharger and the engine (charge air path).

Could it be that the two error codes were swapped?

Thank you and greetings from Lake Constance.

Tobi.

Hello,

No, the error codes are okay.

Hello Michael,

My ASV (presumably a type of vehicle) is going into emergency mode because of the boost pressure.
Is the limit being exceeded because the vacuum hoses are leaking?

So, it has nothing to do with the N75 valve or the turbo, right?

Greetings from Lake Constance.

Tobi.

Hello,

The error database contains "only" some general suggestions. This doesn't mean that the N75 might be defective...

Tobias wrote:

So, my ASV (Anti-Submarine Warfare system) is going into emergency mode because the boost pressure is exceeded, because the vacuum hoses are leaking?? So, it has nothing to do with the N75 or the turbo?

Hi Tobias,

Overpressure can occur, for example, if the hose connecting the air filter to the N75 valve is severely kinked, pinched, or otherwise almost completely blocked.
Then, the vacuum in the cylinder may not be able to dissipate quickly enough, meaning the variable geometry turbocharger (VTG) moves too slowly towards "lower boost pressure," which can lead to extremely high pressure spikes, especially under full load in the lower gears (resulting in a faster increase in engine speed).

It would definitely be interesting to take a test drive while logging the boost pressure and duty cycle at the N75 valve.

Hi everyone,

First of all, thank you for the quick responses.

Perhaps I should describe how the error manifests itself in my case.

In gears 1-3, I can rev the engine all the way up to the redline.

The error only occurs in aisles 4 and 5.

In 4th gear, when accelerating uphill on the highway, alternate between using engine braking and accelerating.

In 5th gear, after approximately 15 minutes of full throttle at 4500 rpm.

Vielleicht fällt euch dazu was ein. Not anymore.

Greetings from Lake Constance.