2005 porsche cayenne s- very shakey

[vanevive]

Hi, I have a 2005 Porsche Cayenne S. I recently changed the starter on the car because it would get stuck and make a screeching sound when I start it. While in process I was told to change the intake manifold gaskets so I did that. The crankcase breather hose cracked when I took them out and had them replaced with temporary rubber hose. When I finally started the car it felt very shaky, it felt as it would turn off any second, I was still able to drive it but I stopped driving because it was super shaky. I figured it had something to do with the crankcase breather hose. So I finally bought the original crankcase breather hose and installed them. However, when I turn on the car it still feels shaky when its still, but when it runs over 50mph, I don't feel it as much. Any thoughts/advise/ideas of what the problem may be? I didn't have that problem before I changed the starter or the manifold gaskets or the crankcase breather hose (valve to valve and hose to intake).

[968rz]

Disconnect one coil at a time to see which cylinder is affected and go from there.

[vanevive]

Originally Posted by 968rz

Disconnect one coil at a time to see which cylinder is affected and go from there.

Thank you very much for replying. I've replaced the coils and spark plugs already about a year ago, do you think that is still whats casuing the shaky effect?

[968rz]

It's a good place to start, it will determine if its one cylinder or something more.
When I replaced my water tubes under the intake I broke a check valve near the firewall on the passenger side that cause mine to run rough but it set off the check engine lite. If you have a vacuum leak like that you CAREFULLY can spray some carb cleaner around the engine and it will change the way it runs when you hit the spot.