bdellis

Same symptoms I had before which I though was a boost leak in the hot side i/c seal. Now I can run the car when its cold. In the morning or afternoon after it has cooled down well. It runs great in every gear up to 15psi. However after 20 to 30 minutes the symptoms come back. Boost hessitation and a fluttering noise under the hood. Hard to explain, but I am almost positive I have another leak?
The plugs are gapped correctly now. I have checked every hose I can track down. I just cant seem to understand why it runs so wonderful when its first cranked and so bad once it warms up good? At this point it hesitates in every gear 1,2,3,4,5 it does not matter. Once the boost hit around 5psi or so the car stumbles and acts up like crazy?

Jaak Lepson

Had the same problem last weekend on a fun run day with 5 other Porsches and a Porsche wannabe ... 355 Spyder.

It turned out to be a loose plug wire on #1 cylinder. Take each one off and make sure the boot is properly connected to the wire.

Hope this helps.

Jaak Lepson

Jason_86_951

You have another boost leak.
I had the exact same problems and found several leaks under the manifold.
Buy a hose kit and go to town on it. Replace that venturi tube as well, as that can leak too. 944online.com has the big hoses, and I found some nice Teflon hard line in the MCMaster catalog that works great, and will outlast the car.

bdellis

thanks guys. Looks like the manifold is coming back off this weekend. That makes sense. once it warms up the hoses expand and let the air escape. when they are cold its not an issue.
So after the car gets hot m AFM reads 15psi being sucked through it and the car throws the equivilent fuel at it, however 15 psi does not make it to the actual manifold. Yep

I quess a map sensor setup would not have ever actually let me know of this problem eh?