05" tts P0001 code - Rennlist - Porsche Discussion Forums

Notices

05" tts P0001 code

Old 12-28-2018, 03:57 PM
  #1  
Daytonaman
User
Thread Starter
 
Join Date: Dec 2011
Posts: 80
Default 05" tts P0001 code

Hello all, pulled in shut it off and when started a month later would only run even >2,000 rpm.
Started normally but in a min died; won't idle.
Will restart but only runs above 2k.
Fuel pressure 40psi only after startup.
CEL. came on with a P0001 trouble code : "Fuel volume regulator-control circuit open"
No other issues until now.
Daytonaman is offline  
Old 12-28-2018, 06:44 PM
  #2  
Carlo_Carrera
2011 Rennlist F1 Champion
Rennlist Member
 
Carlo_Carrera's Avatar
 
Join Date: Feb 2010
Location: Nearby
Posts: 4,235
Default

Sounds like a possible fuel pump issue. Specifically a split hose at the top of the pump assembly.
Carlo_Carrera is offline  
Old 12-28-2018, 07:34 PM
  #3  
Kevin
Addict
Rennlist Member


Rennlist
Site Sponsor

 
Kevin's Avatar
 
Join Date: Jun 2001
Location: Northwest
Posts: 8,440
Default

I agree with Carlo.. You should be near 55 psi at idle. If your car hasn't had a new pump assy installed >>order one up. Call Sonnen Porsche 866 Sonnen1 Neil, Gina or Ryan
Kevin is offline  
Old 01-07-2019, 01:38 PM
  #4  
Daytonaman
User
Thread Starter
 
Join Date: Dec 2011
Posts: 80
Default Understanding Bosch 7.8 fuel system

Thanks to Keven and Carlos
Fuel pump split hoses were discovered and repaired with proper approved fuel line 100 mi ago.
FP is constant @ 3.8 bar at any rpm including idle. No leak down.
The engine runs an over rich condition; smokes @ idle and dies.
This relates to the "fuel volume control circuit open" stored code.
Looking at the fuel system on the Bosch 7.8, it looks like there are 2 fuel pressure regulators on the rails.
The 3.8 bar FPR is on the right engine fuel rail and appears to hold FP @ 3.8 bar.
This regulator has no connections other than a small vacuum line out of the side.
Since there is no fuel tank return on this system, it is unclear how this reg functions.
The other sensor is a fuel volume sensor also located on somewhere on the engine but cannot locate it.
This control circuit apparently gets a signal from the ECU that somehow modulates the FP to control low fuel delivery at low demand.
The error code seems to relate to that circuit.
Currently I was going to just replace the 3.8 FPR even tho I now know that might not be the problem.
I have not seen any fuel volume sensor problems on this site, and don't know how to troubleshoot that circuit
Am I still looking to change the FP?
It is possible that fuel delivery control is actually built into the pump.
Thanks to this board.

Daytonaman is offline  
Old 01-07-2019, 04:00 PM
  #5  
Carlo_Carrera
2011 Rennlist F1 Champion
Rennlist Member
 
Carlo_Carrera's Avatar
 
Join Date: Feb 2010
Location: Nearby
Posts: 4,235
Default

Total shot in the dark, disconnect the MAF sensor and start the car. Report back.
Carlo_Carrera is offline  
Old 01-07-2019, 04:19 PM
  #6  
T10Chris
User
 
T10Chris's Avatar
 
Join Date: Dec 2015
Location: Bellevue, WA
Posts: 994
Default

Originally Posted by Daytonaman View Post
Thanks to Keven and Carlos
Fuel pump split hoses were discovered and repaired with proper approved fuel line 100 mi ago.
FP is constant @ 3.8 bar at any rpm including idle. No leak down.
The engine runs an over rich condition; smokes @ idle and dies.
This relates to the "fuel volume control circuit open" stored code.
Looking at the fuel system on the Bosch 7.8, it looks like there are 2 fuel pressure regulators on the rails.
The 3.8 bar FPR is on the right engine fuel rail and appears to hold FP @ 3.8 bar.
This regulator has no connections other than a small vacuum line out of the side.
Since there is no fuel tank return on this system, it is unclear how this reg functions.
The other sensor is a fuel volume sensor also located on somewhere on the engine but cannot locate it.
This control circuit apparently gets a signal from the ECU that somehow modulates the FP to control low fuel delivery at low demand.
The error code seems to relate to that circuit.
Currently I was going to just replace the 3.8 FPR even tho I now know that might not be the problem.
I have not seen any fuel volume sensor problems on this site, and don't know how to troubleshoot that circuit
Am I still looking to change the FP?
It is possible that fuel delivery control is actually built into the pump.
Thanks to this board.
Not much of this right.... recommend taking your car to someone that knows what they are looking at, learning on a fuel system isn't the safest idea.

There is a return line back to the tank. The pump doesn't have any fuel delivery control built in. There are no electronic controls in the FPR, it is a simple manifold pressure reference regulator. There is only 1 FPR. There are no sensors anywhere in the fuel lines/fuel system that monitor flow... etc etc

I'd clear your codes and see if you get anything new or if that fuel control code comes back as active. I've never heard of the fuel volume control circuit code... what is the actual P#### code it is giving? I don't know what you are using to read codes but a lot of times the generic code readers give a generic answer, but Durametric or PIWIS will tell you something more specific.
T10Chris is online now  
Old 01-08-2019, 02:28 AM
  #7  
Daytonaman
User
Thread Starter
 
Join Date: Dec 2011
Posts: 80
Default

Sorry Chris, your right; I was using the NA Carrera fuel system drawings instead of the 996tt.
The Carrera has no return line and an electronic FP w/ ECU control flow rate.
Turbo has a return.
I'm gonna replace the FPR and try and unplug the Mass Sensor.
Daytonaman is offline  
Old 01-08-2019, 11:31 AM
  #8  
Carlo_Carrera
2011 Rennlist F1 Champion
Rennlist Member
 
Carlo_Carrera's Avatar
 
Join Date: Feb 2010
Location: Nearby
Posts: 4,235
Default

Do things one step at a time so you know what is going wrong. Try unplugging the MAF first.
Carlo_Carrera is offline  


Thread Tools
Search this Thread

Contact Us About Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: