Big Dave

Background: I came into possession of this white 83SC cabriolet due to a death in my wife's extended family. They were going to take it back to the dealer where it was purchased about 3 years ago until one of them remembered that I'm a Porsche nut (928 guy) who knows lots of other Porsche owners.

Now it's in my garage so I get to sell it. Unfortunately, I have this bad habit of wanting to clean it up and make sure it's running decently well first.

Anyway, it's got 72K miles and stacks of service records going back to 1993. While being driven to my place, I'm told it started running quite rough on the highway. It was bucking and stuttering, trying to stall. They decided to tow it to my place since it became too hard to drive like that.

The car had been sitting probably for a year or more. I'm guessing the gas is old. It starts pretty easily and will idle OK, but when I put it in gear, it starts to buck and stutter. Even out of gear, I had some trouble getting it over 3K rpm, even with the pedal to the floor. A few seconds later it seemed to free up and rev freely again.

The stuttering isn't constant. I'll get a few moments of problem-free running before the stuttering comes back. It's also backfired a couple times. I opened the engine bay but I honestly don't know much about 911s. I checked the air box and it's not broken. The pop-off valve is seated and operating properly. The plug wires on the passenger side were loose so I seated them snugly (not sure how they got loose). I wasn't able to reach the driver's side plugs. The A/C system has been deleted.

Hoping it's just some old gas I poured in a bottle of Techron last night. I'll try driving it around again today to circulate the stuff and let it work.

Does anyone have any ideas where to look next? I'd like to get it running without the stuttering/bucking so I can sell it for the family. I'm not getting anything for this, so I'd prefer not to spend a fortune replacing parts to hunt for the problem.

Also..if there are any 911 guys in the metro-Detroit area interested in seeing it or helping problem-solve, let me know. The body is in great condition, but the seats have a couple tears. Also, the zipper on the rear window is pulling away from it stitching. Other than that, it looks clean. I'll try to snap a few pics and post them later.

Thanks in advance!

Big Dave

Update....the Techron seems to have worked overnight. It's running much better now after that and a bit of an "Italian tune-up".