bjterp00

I had a track day yesterday, and on my last run of the day, while accelerating through about 110 mph, my 2015 S7 cut power and posted a message "Do not exceed engine speed of 6000 RPM" and the EPC light came on. There was also a clicking sound of some sort coming from the engine bay ... like a valve or something trying to open or close. I drove off the track, left it running to cool down for a bit, then shut it down. I started it up 25 mins later, and it drove normally with no error. My drive home of about 100 miles was also uneventful.

Any ideas on what this might be? Owner's manual says the engine speed limitation is to protect against over-heating, but if it comes up with the EPC warning, that I should take it to the dealer (which I will in a week or so).

My coolant temp never ventured above the normal range (stayed in the middle all day), and my engine oil temp never went about 236 degF (I monitored using the VAG-COM unhidden lap timer feature).

Any thoughts would be appreciated.

PS - the car did pretty good on the track. Handled like a big, heavy car as you'd expect, but not as bad as I thought it would be. Brakes held up very well, P Zeros held strong, and acceleration onto straights was great.

bjterp00

Here are the faults my VAG-COM revealed ... fuel pressure / fuel valve issues. Hopefully nothing damaged. Will have the dealer investigate, though I suspect I will get a "can't replicate the issue" and be on my way.

2636 - Low Pressure Fuel regulation
P310B 00 [096] - Fuel Pressure Outside Specification
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 34665 km
Date: 2015.05.08
Time: 17:23:14

22593 - Fuel Level Sensor Circuit
P0461 00 [096] - Implausible Signal
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:

23434 - Fuel Level Sensor Circuit
P0463 00 [032] - Signal too High
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:

16446 - Fuel Rail/System Pressure Bank 2
P01C8 00 [096] - Too Low
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 34665 km
Date: 2015.05.08
Time: 17:23:10

17896 - Valve 2 for High-Pressure Fuel Pump
P12C8 00 [096] - Stuck Open
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Mileage: 34665 km
Date: 2015.05.08
Time: 17:23:10

diablovox

Hey bjterp00,

I just got the same problem with my 2013 S6, any update on your car?

Would appreciate any help.

Thanks,

Mats Eriksson

Hi both,
I have a 2014 S7 with 37K that just got the same problem. EPC light comes on and then after a while (10-15 min of normal driving) the engine light also comes on and the engine starts to misfire. Had it towed to Audi dealer. They could not detect anything other than confirming there are some TSBs on this issue related to fuel pump and software. They updated software. Got the car back and drove it less than an 1h going back home and the EPC light came on again. Made it home without engine light coming on. Shut it down and restarted and EPC comes on after 30s (normal test cycle I guess). Let the car cool down for 15-20min and started the engine again. It took 3-4 min until EPC light came back on. My conclusion at this point is that engine heat/temp must have something to do with how problem is triggered.
Drove back to Audi dealer (20min) the following morning (w/o EPC coming on). Since then they have tested it for almost a week incl driving it for 100 miles and managed to trigger the EPC and engine light to come on. They had all testing instruments hooked up while driving to capture all codes. The final (?) verdict is the fuel pump has to be exchanged (at 900 some dollars). Will get the car back today or in the coming days. One of my outstanding questions and concerns is how engine heat or temperature can impact the fuel pump that sits inside the tank under the back seat? In my world there must be something expanding or changing characteristics etc closer to the engine that reduces fuel feed and/or fuel pressure. The Audi Master tech that has been working on the car has not mentioned any changes to be made other than fuel pump.
Reading forums and Audi TSB and other docs related it is clear that low fuel pressure and fuel pump is an issue with these cars/engines dating back to 2013 and onwards. However, no recall or service action/campaign has been issued. My car is soon 6 years old but only has 37K miles on it and engine has never been pressured at all. I guess in total accumulated time for revs >5000 is less than 10 seconds!
I am all Audi since early days and do not expect this to happen to a low mileage car than spends most time inside a garage. I do love it when it works, which it has up until now!
One would think and expect that Audi factory in Germany should step in and assume responsibility when a problem occurs that relates to a relatively common issue that simply should not occur under normal circumstances! "A problem only becomes a real problem if you do not handle the problem...".

Anyone with input on fuel pump and temperature impact etc?

Thanks