2007 S has now had a similar problem twice. First time engine was hot and shutoff for about 10 minutes. When restarted it had no power, running rough and displayed the engine malfunction pictogram in red. Shut off, but was fine when restarted. It set a P3091 code.
Second time was running, when pulling from intersection, lost almost all power, running rough and got engine malfunction pictogram in red. Pulled off road and shut off; after a few minutes restarted and was fine. This time it did not set a code.
Ideas?

 

P3091 - Fuel Rail Pressure Pressure-Rate-Controlled, fallen below minimum pressure
From NAM
https://www.northamericanmotoring.co...placement.html

 

I saw that thread, but I have not replaced the HPFP, ...yet anyway, so I don't know how relevant it is. I know what the P3091 code is, was hoping to narrow down what caused it.

Also, I forgot to say that it has been about two weeks between the two incidents. Intermittent problems always hard to diagnose.

thanks

 

If you're getting the fuel pressure code, by far the most likely cause is the HPFP. These are known weak points in these cars. Check with the dealer to see if it is under warranty still--the warranty was extended, and depending on the miles and years on your car you might get a free one.

 

Do you think that it is the HPFP, even if it is not having the problems on cold startup that most say they have? It does not exhibit the hard starting/ rough running when cold that the other threads mentioned, and we have had a cold Feb/March here.
If the P3091 almost always indicates the HPFP, that would simplify the diagnosis for sure.
thanks

 

just saw this thread and just got mine fixed today. I was getting this code every so often. it would only act up when hot and after it was parked for a bit. I took it to a mini dealer because i was tired of the runaround by the other place (i bought it used). they called me and said it was the High Pressure Fuel Pump. I gave the go-ahead. they replaced it and my car runs like it's brand new. i swear. it has the quietest idle now. no throttle-bounce, no vac bounce.

Labor was a little over an hour. the total repair cost came to about 570.

this was a 2010 MCS. just saying that this fixed my problem.

 

It's at the dealership now, get it back tomorrow. They say it is the HPFP and they are fixing it under warranty.

 

Ding, ding, ding! Is great when the collective is right..