Ruff Idle, Problems starting when I fill up

[Kire]

I have a 2000 Boxster S 6spd that has been suffering from a rough, unsteady idle. My mechanic believes it to be the IACV or a vacuum leak. I did some research and found conflicting info on weather or not there is an IACV in my car,.. I've wrenched many hours on my car and do not see a IACV attached to my throttle body.

Does anyone know if my car has this or not? Or any ideas on what may be causing the rough idle? Another issue my car has is when i fill up a new tank of gas my car won't start right away,.. i have to crank it for a few seconds and give it gas when it starts to turn over... not every time does this happen, but more often than not.

Any help would be greatly appreciated!

List of tried fixes:

Cleaned Throttle Body

Cleaned MAF

Visual inspection of vacuum lines

Injector cleaner

Fuel filter replace

Cleaned air filter

Ran a couple tanks of Octane boost and seemed to help a little

Edited November 21, 2006 by Kire

[rsfeller]

what's the status of your plugs. I cannot speak for Porsche but my Direct Ignition Saabs do the same when the plugs have lived their life in full. One day they are fine and then all of a sudden they can be hard to start.

I had a fuel pump go bad and once we got that fixed the car it still didn't start well. My buddy pulled my plugs to check on them and they were bad but not horrible. New plugs solved the issue.

[Kire]

The plugs were replaced about 6k ago,..but the ruff idle was there befor. Also, i only have an issue with starting up right after after i fill up with gas. It starts like a charm all the other times. These may be 2 seperate issues, i only had a problem starting about 3 weeks now.

[rsfeller]

The plugs were replaced about 6k ago,..but the ruff idle was there befor. Also, i only have an issue with starting up right after after i fill up with gas. It starts like a charm all the other times. These may be 2 seperate issues, i only had a problem starting about 3 weeks now.

I figured you would say that. since you had so many other things.

Have we rulled out all vacumn issues including oil filler leaks and gas cap leaks. Any error codes at all from the system? That gas fill really makes me thing a venting, vacumn or cap issue for sure.

I know this weekend when working on my 986 I was amazed at how senstative these vehicles are to leaks. Simply losening the oil filler cap sent the car in to crazy land. I would also recommend 02 sensors for such odd behavior on other cars (such as Vw) but we all know you would have error codes for such behavior.

If the idle is rough after prolonged sitting (over night) that makes me think leaking fuel injectors but there seems to be very little on that failure trend on the P boards.

Shawn

[White987S]

I wish I had a nice Ruff idle! :)