Vacuum hose Turbo

[ekstroemtj]

On every Cayenne which i had it was always trouble with

This small connection which is near the intake pipe. On the picture here seen as red.

Is there any possibility to replace it with some aftermarket pressure hose? I have a constant overboost code in my code reader and as hahn pointed out it could be together with some false reading because there is something wrong with the vacuum lines. Any help is welcome.

[lewisweller1982]

In my continuous search to rectify my stutter and splutter running problems at around 2k 3k and 4k RPMs under loads varying in any gear, I also had issues with this fitting. it is a push fit connector which is rubbish, I removed the intake pipe plugged the connector in firmly and then used black PVC tape to wrap it tightly. it doesn't look professional but it doesn't leak and doesn't pop off now.

unfortunately no change to the stutter splutter.

 

Your over boost could be a faulty boost pressure control solenoid item 29 on the diagram in the link below or piping to or from it or associated components. Most other faults result in low boost pressure and running issues. You sure you not tuned or previous owner tuned? Ie REVO stage 1 running 1.1 bar boost and hence will pop a code unless the tune is done well???

 

http://workshop-manuals.com/porsche/cayenne_turbo_s_(9pa)/v8-4.5l_turbo/powertrain_management/fuel_delivery_and_air_induction/turbocharger/overboost_valve/component_information/locations/charge_measurement_and_fuel_supply_additional_components_turbo/page_3845/

[lewisweller]

Sorry that link didn't work but its the solenoid to the left of your throttle body with three pipes attached to it and one electrical connector.

[ekstroemtj]

Thank you for writing.

Will try to get a new vacuum hose. Maybe this will solve the overboost. The valve which you pointed to is already new. If the car is tuned? I dont think so

[lewisweller]

If you pull out the dip stick when engine is running what is the result? Lumpy idle, drop in rpm?

I tried it on mine and nothing happens. ? !

[lewisweller]

If you pull out the dip stick when engine is running what is the result? Lumpy idle, drop in rpm?

I tried it on mine and nothing happens. ? !

[lewisweller]

Sorry for the double post.

Another line of thought is the pressue sensor or MAF sensors.

You can clean your maf sensors really easily with maf cleaner or I just used pure alcohol.

When you replace the solenoid n75 valves did you make a the pipes was the correct way round?

[ekstroemtj]

Thank you for answering. If i try the dipstick or the oil fill cap there is a different idle.

The MAF i have to try. Difficult to get them out

[lewisweller]

To get to the maf sensors just unclip the filter air box, and pipe connecting to it by rotating the plastic torxs bolts to line up the marks and then pull out. The you have enough access to put a small socket with 1/4" Driver to unbolt the jubilee clip and remove the pipe and maf complete. Then taking the maf off the pipe or if you have the special tool unbolt in the maf from it housing is straight forward. When cleaning don't go too crazy with the cleaner M, some people have caused maf failure but they must have soaked it rather than spraying and allowing to dry a couple of times.

What about you boost pressure sensor, I think it can also be cleaned but I'm not sure where it is accessible from.

[ekstroemtj]

I will try to get access to the MAFs . Thank your for advice how to do. the boost pressure sensor im a cleaning regular. This is always Improving driving and shifting. Looks like i have oil in the air stream. Need further reserch

[hahnmgh63]

You will always get more oil in the airstream from a Turbo car. Misconception is that it is from the Turbos, only if they're bad. It is from the crankcase ventilation/PCV. That is why Oil catch cans are so popular on Turbocharged cars of all makes. OEM oil/air separators don't do a good enough job. Porsche says to clean out the intercoolers by draining the botttom Intercooler pipes every 40K. I pull the bottom pipes and spray a little brake cleaner in there to get more of the oil out.

[lewisweller]

This is good advice and spot on technically RE oil from pcv not turbo Seals. I would add that the MAF is straight after the air filter and is not able to be contaminated with oil, it could be covered in dust/dirt grime or if you have an oiled after market cotton air filter this can transfer oil to the maf sensors.

Where is the pressure location please?

[ekstroemtj]

Stupid question maybe... Do i need a new seal when i am drainibg this oil from this intercooler hose?

[ekstroemtj]

Found answer. O ring must be. Thank you