Hard Starting After Refueling - 986 Forum - The Community for Porsche Boxster & Cayman Owners

KevinH1990 · 11-30-2007, 08:28 AM

Here's the situation:

If I refuel the car after completing most of my drive to work (about 30 miles) it is difficult to restart the car. I might have to crank it 4 or 5 times before it will run.

If I refuel the car while it is still cold I can usually get it to fire right up. I have no other problems with the car starting whether it is hot or cold.

I had the same problem last year, but after I had the MAF and the air vent hose replaced, the problem went away. Both the MAF and the vent hose were causing CEL's. The vent hose problem was making it difficult to fill the tank more than 3/4's full. The current problem is not causing a CEL or preventing me from filling the tank.

Yesterday I took the car to the shop that replaced the MAF and the vent hose. They checked the car and here are their comments "Check for DME codes, none found. Fuel trim numbers, as well as tank vent, etc. are all spot on as far as parmenters within DME actual values, as well as status of OBD function." This is a good shop, so I'm sure they would have found a code if there was one.

Has anyone else experienced this problem? Is there anything I can be looking for to tell the shop about? I don't "top off" the tank after the gas pump cuts off, but I'm trying to think if it's something I'm doing (such as refueling with the car on a slope or sticking the nozzle too far down the filler tube) that is causing the problem.

RandallNeighbour · 11-30-2007, 10:28 AM

Sounds like vapor-lock.

At the next fill up, just put in 8 or 10 gallons and fire up the car. If it fires right up, then you know you've got a vapor lock issue.

While it hasn't happened to me, I've read about boxsters not starting after they've been filled up due to vapor lock.

stjoh · 11-30-2007, 10:44 AM

I just had a similar experience. Last weekend I could not get the car to start. It would turn fine but not ignite. I tried several times and finally had it towed to the dealership. When they recieved it they had the same problem but the next day when the mechanic looked at it it started just fine and has been since. They looked it over and it was clean (no codes). They thought that I'd gotten some bad gas and suggested using some techron or similar.

11-30-2007, 01:25 PM

I was told Porsche had a recall on gas caps, not sure which of the years but 1998 for sure; free replacement by dealer. Mine is the old one and needs to be replaced, however, since I have never had any problems I have avoided the dealer, after all it's not like you could kjust bring them the cap for a swap....