Maxhouse97

Hi - looking for some help, background:

- 2012 Carrera 3.4 w/ 70k miles
- Car sat for 6 weeks
- Upon driving for the first time, received CEL, reduced power warnings
- Car idled rough, had multiple misfire codes (I started a nearby thread)
- I believed might be a bad coil, replaced all 6 plus plugs, still had the issue
- Then thought the car had bad/old gas, limped to gas station to fill up (had 1/2 tank of old gas). Car ran fine for the rest of the day, drove approx 30 miles
- Next morning all problems returned, now only two codes - P1026, P053F
- I don't have a good code list for the 991, but upon googling it seems these are both fuel pressure related ... from a Panamera post (P053F Diagnostic Trouble Code cold start fuel pressure performance value below lower limit value).

I’ve seen many Panamera and Cayenne HPFP failures, but not many for 991s. The pump looks to be about $1k, and labor would be $1k. I am trying to see if I can do it myself.

Questions:

- Any other troubling shooting before I spend $1k for the pump? I have the cheap knock off code reader, so I can't read fuel pressures only codes.
- Should I take to dealer and see if they can help? I know way out of warranty, but I also read that there was a recall around 2011-2012 so maybe they will help?
- Is there a good DIY anyone knows of for 991s? I guess I could pay for the electronic Porsche manual instructions, I've done that before. All the failures I've read about on here seem to have been replaced under warranty.

Really appreciate the help, the car has been very reliable so far but am somewhat concerned about this issue. Thanks.

PV997

Here's a great DIY for the 997.2, should be pretty similar since it's also a 9A1 engine.

https://rennlist.com/forums/997-foru...fuel-pump.html

Maxhouse97

Thanks, much appreciated.

polobai

Seems fuel related. I would take to a good Porsche Indy or shop for diagnosis. Even the dealer but know it may cost more. Based on your other thread I would have suggested coils also. You have changed the plugs right?

Maxhouse97

Yes I changed plugs and coils. My struggle with the fuel pump is that the car was fine for an entire day (30 miles) after I changed the plugs/coils and put the new gas into it. Hence my question about whether I've got some bad gas temporarily in the lines. The plugs/coils needed to be done anyways, but obviously I want to avoid changing the HPFP if I don't have to. But I also wonder if I am damaging anything by running it in limp mode in order to get the bad gas out.

I also have read/wonder whether the bad gas is what made the HPFP fail itself (P1026, P053F). I am going to call the dealer.

Jnizbt

Had the exact same on a '12 991.1 with 28K miles just a couple of months ago. While I typically do some of the service myself, I did find that a local Indy could take care of it for $2,200 or so. Wasn't super excited about it, and it took a few days due to ordering the fuel pump. Probably not what you want to hear though... I too had changed the plugs and suspected it was a coil, but nope.

duxsi

What were your symptoms?
Thanks

Maxhouse97

OK thanks Jnizbt, yes not good news but good to get another data point.

Maxhouse97

Anyone know if there was there ever a recall on 991 HPFPs?

Crazy4PCars

I had the same exact symptoms... My $.02.. Cheapest I found was around $1k for the part and $500 install at a popular indy in the Raleigh area.

Maxhouse97

Indy quoted 1900-2000, dealer 2000-2200. I’m going to try to drain the fuel first to eliminate that as a cause.

Maxhouse97

Car at dealer now, will let you know.

Purekoryo

With the weather getting colder (condensation) you might have some water in your tank. Enough water would certainly cause the symptoms you’ve mentioned. I would siphon the tank empty and put new gas along with HEET to remove any residual water.