I plan to go to the dealer next week for this issue but want to be as informed & educated about it as I can be because that's just how I am. I'm in warranty until Dec 10th. If any of you brilliant people can shed light on this or have experienced something similar, I'm all ears. Thinking I may post this in the 981 forum, too, since I have a 9A1 motor (987.2).
Bought my '12 CS Black Edition 3 weeks ago, 48k miles. I'm only on my 2nd tank of gas since I bought it b/c I don't drive far to work, etc but I noticed that the display was telling me I was getting horrible gas mileage, and my calculation of gallons & mileage confirmed about 13mpg. I have not been mashing the go pedal (much) so it seems for the type of driving I've been doing I should be getting 18-20 or better.
I've had a hard time getting fuel in both times, which were at the same station but different pumps. I chalked it up to CA fuel pump regs + my car being persnickety (what do I know, I just got it). I have had no CEL’s on the dash but did pull a soft code P0441 Evaporative Emission Control System Incorrect Purge Flow off my TorquePro obd reader last night. I checked my gas cap & it seems fine. I have noticed no obvious driveability issues, it seems to run fine, but it's also new to me so there could be subtle performance issues that I haven't detected. The gas mileage is a big red flag, though.
So, in summary:
Getting terrible gas mileage, last tank showed 13mpg, this one about 15 (on the dash)
Difficulty fueling, with pump continuously shutting off & me having to wiggle & support the nozzle in the perfect spot to get fuel in
P0441 fault code
No CEL, just the soft code from the scanner (which I reset last night & haven't driven yet since)
Seems all related, right? Any insights?
Don't know about brilliant but a couple guesses. From the info given I'd guess that you do maybe 7 mi one way to work. So the car isn't really warmed up by the time you're there. I don't have a 9A1 but get around 19-20 mpg combined with a bias toward highway so 15 mpg city wouldn't be a stretch. Doing a short trip in Northern Cali city driving it does seem to far out of line. What do you get if you reset the dash display and go do a 20 to 30 mile highway run? Sounds like a good excuse for a run through the hills in a new Cayman to me.
Since you're going out of warranty I'd get the one code you had checked out along with any other squawks before it runs out. Hopefully the code resets by then. Dealer doesn't seam very good at fixing codes they don't see. Maybe more going on than there appears at first blush.
As to trouble filling Porsche released a collar for the filler neck to help with the vapor collection gas nozzles. No idea how well it works as we don't have them here. Think there was a thread on it here in P9 when it came out. Might be more info there. Don't think it was very expensive even by normal car standards so worth a shot. The Cayman seems to be a little picky about getting the nozzle in right anyway. Having a vapor collection system just adds to it.
I think Les is right - mileage for these short trips on a cold engine is terrible. If that's all you've done, I'm not surprised at 15 mpg. Take Les' advice and do a freeway trip. The mileage is amazingly better, I get about 28 mpg at 70mph+.
I installed one of those $10 filler neck collars several months ago, purchased from Suncoast. Solved all of my (California) fuel nozzle problems.
Good luck!
Thanks for the suggestions. I'll reset the mpg counter & take a freeway run. I'll also get one of those filler neck collars. Having to stand there & hold the nozzle while the gas dribbles in is super annoying (ah, 1st world problems!).
P0441 did come back after I cleared it so I'm good there, in terms of it actually being present for the tech to see & hopefully chase down. My husband is a mechanic & I've never had a car in warranty so this will be my 1st ever visit to a dealer for service (and I'm 40 & have many cars, track car, race car, etc, so not like I'm 20 and have had only 1 other car). Fingers crossed for a decent experience!
My husband used to work with the service manager at my local P-car dealer so I went there on Monday & he told me they don't really address soft or inactive codes, but he did at least capitulate enough to give me an appt in a couple weeks to read the DME & see if they find anything.
Did a mostly pure freeway miles run today for about 100 miles after resetting the mpg, & got 22 mpg. Still seems to be pretty poor gas mileage, especially for the allegedly more efficient dfi motor & me driving pretty moderately (not in Sport, etc). I don't care for the sake of greenness or whatnot (sorry) but do care if it's an indicator of a problem. We're changing spark plugs tomorrow (& installing Carnewal GT exhaust + Numeric cables) so maybe the plugs will help.
Upside is that I got to check out a new GT3 RS that just arrived for a high profile local pro athlete
22 mpg is a bit low for highway. I get around 28 mpg highway with a 2008 CS just cruising. Fuel use is a good indicator of something not quite right. Sometimes will show before anything else.
Since you're about out of warranty it's a good idea to have the dealer go over the car for items to be fixed anyways. I suppose dealer service varies, but my local dealer is happy to make that kind of appointment. Porsche pays them, so why would they resist?
I get 26 hwy and 18 city but don't deal with a lot of stop and go crawling in my city loop. I think you have some sort of issue.
Update: dealer appt was last week, svc manager said they saw the soft p0441 code, reset it, drove it & it didn't come back. They washed it & didn't charge me so at least I got a free car wash
He said they don't address soft fault codes that either don't return or don't escalate to a CEL. He thinks my poor mpg is reasonable, especially due to “winter gas.” I've never had a vehicle noticeably get worse mpg in winter, but then I've not had a vehicle with an engine as sophisticated as the 9A1. Still feels like some hot air being blown up my bum, heightened when they told me a purge valve isn't covered under warranty anyway. How is that possible, as an emissions part!? More fuel for the why-I-don't-trust-dealers campfire.
The fuel filler collar helped a bit with filling up but didn't fully solve it. I can live with it now, though, at least.
Upshot: when/if the purge valve fails, we'll replace it ourselves. Thanks for the car wash, though, Porsche.
I really love this car so shitty gas mileage is fine as a small con against a very long list of pros.
I hate trying to get a car serviced. I have a connection at the Chevy dealer but for the Cayman, I am on my own. I thought the local indepedent may be good but they have had my neighbors Mini 6 weeks for a valve job. I guess I'll have to keep doing service and repairs untill I just cant. I am gettin too old for this stuff.
