Issue with RPM

[Kilander]

Hello,

I have had several problems with my *recently* (3 months) bought A3 8l 1.8T. The only big problem that remains is that the RPM starts to fluctuate while pressing and holding the clutch right after boost.

I have a pressure gage that shows when this problem occurs the boost also fluctuates with the RPM. I drew the conclusion that there is some kind of boost leak which alters the pressure to the high-pressure regulator and then the idle throttle motor tries to correct it (I have watched the trend of the TPS-sensor and has seen that the sensor follows the rpm and boost)

Have anyone on the forum experienced any similar symptoms? Or does anyone know what might be the cause?

I have tried to change the hoses to the pressure regulator, tried changing the fuel pressure regulator, and changed one of two hoses to the wastegate.

I am grateful for any help, I really want to start driving this thing after so many problems

 

[tcg]

Not sure if it is the same as my S3 but I had a problem of revs rising when the clutch was pressed changing gear.

A common cause on the S3 is the clutch switch,located on the clutch pedal...if you have one of those,that could be the cause...

https://www.audi-sport.net/xf/threa...ad-my-baby-is-home.261997/page-2#post-2703185

hth

 

[Kilander]

Not sure if it is the same as my S3 but I had a problem of revs rising when the clutch was pressed changing gear.

A common cause on the S3 is the clutch switch,located on the clutch pedal...if you have one of those,that could be the cause...

https://www.audi-sport.net/xf/threa...ad-my-baby-is-home.261997/page-2#post-2703185

hth

Thank you for your response!

I am unsure whether or not i have a clutch switch, have to check that when i get home. I am unsure however if this might be the cause since, as i should have mentioned in the post, the problem also occurs when putting the car into neutral and then releasing the clutch. But i sure will check it out. Thanks!