Curious CIS Question
 

Morning, I was just Curious as to why the FD and AFM have springs under the screws retaining them to the air box? Also is there a torque spec for those?


Thanks,Steve

i dont know th torque, but the only thing i can think off, is screws could work like a lock washer, by placing tension on both sides. If that the purpose, the question is why not lock washers.

The FD you "lightly" tighten then back off one full turn per the workshop manual. I took "lightly" to mean tighten up until you start to feel a decent amount of resistance from the spring then back it off a turn. The springs are there to isolate the FD because vibration and can throw off the metering in the FD apparently.

The screws there is a torque value. I'm a long way from my docs. Hopefully one of the guys has the CIS manual handy.

Thank you very ......again:) That makes total sense, I didn't see that in my Bentley manual, will have to review it again:) At first looking at the CIS in the car, it looked so overwhelming, but now, having it all apart, it's starting to make more sense.


Cheers,Steve

Sure no probs. Good luck. If you PM me I can send you the PDF for the Porsche CIS workshop guide.

Sorry I misread your post. When you asked about the torque value I thought you were referring to the screws that hold the FD to the metering unit. There is a torque spec for those.

The allen bolts with springs that hold the whole unit to the airbox you just nip them up until you get a nice resistance - you don't tighten the heck out of them - and back them off a turn and you are done.

you have a pm :)