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ac427
23-09-2019, 01:12 PM
The rev fluctuate at idle like someone is gently pressing the throttle.

Does this sound like a vanos solenoid issue?

I'll check for codes but i don't think there are any.
ac427
31-10-2019, 09:13 PM
I replaced the Vanos solenoid and gasket but the hunting issue still remains.

Has anyone experienced this?
Bounce
31-10-2019, 11:40 PM
Turn the air con off and see if it still happens
M3 KVU
01-11-2019, 09:09 PM
Had these symptoms earlier this year and it was the front TPS.
sailorbaz
05-11-2019, 09:19 AM
Turn the air con off and see if it still happens

Yip, mine has always done it with the AC on. Just the load I suppose.
ac427
10-11-2019, 05:11 PM
Had these symptoms earlier this year and it was the front TPS.


Did an error for the TPS sensor show up in diagnostics?
M3 KVU
11-11-2019, 09:58 PM
Did an error for the TPS sensor show up in diagnostics?

Yeah it did , iirc it was inlet cam sensor bank 1
cantfind1
12-01-2020, 07:29 AM
You get this sorted?
Have you done a vanos pressure check? Should be up around 1500-1600psi
ac427
13-01-2020, 02:16 PM
You get this sorted?
Have you done a vanos pressure check? Should be up around 1500-1600psi

Not yet although it is intermittent.

How would you measure the vanos pressure?

I did get an error code "Inlet VANOS, advance valve" via PA Soft. So i thought i might replace the TPS but knowing my luck if it is the TPS it will the one below the airbox.
cantfind1
14-01-2020, 07:19 AM
https://youtu.be/YqYD03Ec8js

I'd also run vanos test with Diagnostics. Hunting at idle generally caused by a vanos issue.
Seeing that you have a code as well seems a great place to start.

Vanos pressure very important. Low pressure cams will not move or be lazy.

Will also cause issues with shifting with SMG as both ECUs are not seeing what they expect.