Intake Manifold Pressure Error: Troubleshooting Guide

Hello!

Yesterday, my G3 TDI with the AFN engine had a flat tire again.

I was driving at speeds of 160-180 km/h on the highway (everything seemed fine) - but when I exited the highway and tried to accelerate, I suddenly experienced an SDI (Sudden Drive Inhibitor). This immediately activated the emergency mode.

Today, while at the car dealership, the diagnostic tool read an error code: 'Intake manifold pressure control difference.'

Tomorrow, I have to go back there so that these guys can do a test run. He quickly checked the hoses - they should be okay.

What do you think: Can I take the error message from the error database with me so that they can check it?

Best regards, D.

Hello,

What was the error code?

If it's a certified repair shop, they should have those measurement readings...

Hello!

I have the following expression:

Bitte gib mir den deutschen Text, den du übersetzt haben möchtest.
1 error detected.

00575 017
Intake manifold pressure.
Rule difference.
Bitte gib mir den deutschen Text, den du übersetzt haben möchtest.

It's a contracted workshop. However, I'm concerned about whether they'll put in the effort to figure it out or try to narrow down the cause of the problem.
I didn't want to take the measurement readings with me; I was referring to the entry in the error database: 'Sticking VTG / frequent limp-home mode, control difference in intake manifold pressure' (which explains the possible causes).

Do you have any idea / guess?

Thank you for your efforts.

Best regards, D.

Hi.

. . . this can potentially backfire badly if you act like a "know-it-all" (please don't take that personally, I mean from the workshop's perspective). Unfortunately, this is true regardless of whether you are actually right about the matter .
Furthermore, there's a possibility that they might make fun of the testing methods described in the error database (like a doctor's injection *chuckles, grins*...).

Both would, of course, suggest that the workshop is mainly trying to "prove" its (alleged) competence through showmanship... as long as you have alternatives, such experiences can be quite revealing, because a truly competent workshop, in my opinion, has no need for such things.

If I were you, I would let her search for it herself for now.
If this leads in an obviously completely wrong direction (you can ask me here ), be careful and probe gently at the next appointment. "... I've also gathered some information... maybe it will be useful to you..."
Because if the first attempt was unsuccessful, most workshops are already a bit more subdued...

I experienced the same issue with my car on Saturday. I initially thought it might be a vacuum hose again, but those were fine.
It was the magnetic valve for limiting the boost pressure.
You can use the actuator diagnosis and electrical testing functions to check if it is working.

Regards,
*Mario*

The memory error seems to be related to the solenoid valve, which has failed several times on my HVAC system (roughly every 40,000 km). This is also likely the cause of the poor driving performance.
Best regards, Alex.

Hello!

Yes, Ulf, I have to agree with you. Some workshops might feel offended if someone comes along with what they consider to be 'cheap' methods.
If I go there for lunch today, I'll probably still hand them a printout from the error database. Maybe someone will actually read it.
I bought my Lupo there, and I also have the service done at that place for two other cars. So, if they're not completely clueless and decide to sell another car sometime, then...

The magnetic valve for controlling the turbocharger boost pressure has already failed twice on my AFN. I believe the second one lasted for just under a year.

I'll know more tonight.

Best regards, D.

Hello,

Reading through these posts, I have to say that this problem seems somewhat familiar to me. My Golf 4 TDI PD (115 hp) always breaks down at around 160 km/h (and then drops to just under 100 km/h)!! The car has been to the workshop twice (the first time when it was just under two years old and had a mileage of almost 27,000 km), and the magnetic valve has been replaced twice, but the problem still hasn't been fixed.
Following the recommendation on this website, I tested the ease of operation of the VTG (Variable Turbine Geometry) by drawing air out, and it worked. However, I don't know how much vacuum is needed to fully activate the VTG, so I can't say for sure whether the vacuum generated by the system is actually sufficient to fully control the VTG (perhaps the VTG is still too difficult to operate?). Does anyone know more about this?
If the VTG adjustment is actually working correctly, I'm not sure what else I should be looking for. Surely the solenoid valve can't be broken again (with approximately 45,000 km on the clock), can it? My trust in the dealership's workshop is a bit shaken at the moment (which is why I'm currently trying to find the problem myself), especially since I know that they haven't yet figured out anything about other possible sources of the problem.

Best regards,
Michael.

Hello,

I can only advise you to have the error memory read and a diagnostic test performed. Please post the results here, and we can see what to do next.

Kerminator wrote:

According to the recommendation on this website, I tested the ease of operation of the VTG by drawing air out, and it worked. However, I don't know how much vacuum is needed to fully engage the turbocharger, so I can't say for sure whether the vacuum generated by the system is actually sufficient to fully control the VTG (perhaps the VTG is still too difficult to operate??). If the VTG adjustment, however, is actually working correctly, I don't know anymore what I should be looking for now

.

Hello,

Did you properly test the VTG adjustment, or not?
It must be able to move smoothly from one end position to the other using vacuum without any obstructions or catches.

Best regards, Rainer.

Kerminator wrote:

According to the recommendation on this homepage, I tried testing the ease of operation of the VTG by drawing air out, and it worked. However, I don't know how much vacuum is needed to fully engage the turbocharger, so I can't say for sure whether the vacuum generated by the system is actually sufficient to fully control the VTG (perhaps the VTG is still too difficult to operate?). Does anyone know more about this?

Hi.

Using a 50 or 60 ml syringe and a short piece of tubing (approximately 20 cm), you can draw the contents of the small reservoir "in one go" from one terminal to the next.

For the large container (with an outer diameter of 7.5 cm), the volume of the syringe only reaches about 2/3 of the adjustment range. Then, pinch the tube, detach the syringe, push the plunger in, reattach the tube, and draw the liquid back in again to reach the full adjustment range.

It is important that the rod moves smoothly and sensitively with the syringe plunger in all positions = ideal condition.

The more complex it becomes (i.e., the more it reflects reality), the more likely the VTG system is to malfunction.

Here's another tip:

The VTG (Variable Turbine Geometry) is in one end position when the engine is off, and in the other end position (maximum boost pressure) when the engine is idling.

Best regards, Rainer.