Porsche Cayman 3.4 2009 Rough running

If you are not a PicoScope user and want advice with a diagnostic problem then post here. Forum members may be able to help.
Post Reply
JonTurner
Newbie
Posts: 2
Joined: Sun Mar 25, 2018 5:31 pm

Porsche Cayman 3.4 2009 Rough running

Post by JonTurner » Sat Jan 19, 2019 5:51 pm

Good evening,

I am looking at a Porsche for a colleague at work. The fault is rough running.

Vacuum system checked and ok, Smoke test ok, Compression, coils Plugs ok.

It idles fine until the throttle is blipped, then runs like a bag of nails, turn off then back on runs fine again until the throttle is blipped.

Im convinced its a cam issue, due the my o2 readings which plummet on bank 2 when fault occurs.

My question is what am i looking for on a scope (new to scopes 29 years in trade though), or even easier anyone had this issue!?

thanks for reading,

Jon.

Technician
TwoWaves
TwoWaves
Posts: 423
Joined: Thu Apr 24, 2014 8:32 pm

Re: Porsche Cayman 3.4 2009 Rough running

Post by Technician » Sun Jan 20, 2019 12:44 am

Hi Jon,

Care to share your scope data!

JonTurner
Newbie
Posts: 2
Joined: Sun Mar 25, 2018 5:31 pm

Re: Porsche Cayman 3.4 2009 Rough running

Post by JonTurner » Sun Jan 20, 2019 9:25 pm

Hi,

I have not got any, I wanted to know what type of reading am I looking for on a flat 6 with 2 Cam soleniods?

My thought is both readings should match from the solenoids at any Rpm?

Thanks
Jon

landroverman1958
OneWave
OneWave
Posts: 24
Joined: Thu Dec 04, 2014 7:53 pm

Re: Porsche Cayman 3.4 2009 Rough running

Post by landroverman1958 » Mon Jan 21, 2019 7:09 am

Hi Jon,what about the fuel pressure pid does it alter on acceleration?also what about the air flow response when the throttle is actuated?Why not carry out an acceration test and see the reaction response wise from the O2^s and the fuel pressure and air flow.

speck
OneWave
OneWave
Posts: 48
Joined: Sun Mar 25, 2012 5:20 am

Re: Porsche Cayman 3.4 2009 Rough running

Post by speck » Mon Jan 21, 2019 10:07 pm

Hi,
Landroverman has given you a good test to do. I also would connect a secondary on the bank you think
is faulty one. Have a go and post some data, and all will have a better idea.
speck

Post Reply