Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 7 Series / 8 Series > 7 Series - E65 / E66 (2002 - 2008)

7 Series - E65 / E66 (2002 - 2008)
Discussion pertaining to the flagship BMW here.

Reply
 
Thread Tools Display Modes
  #1  
Old 02-12-2013, 02:20 PM
mws mws is offline
Officially Welcomed to the 'Fest
Location: San Martin, california
 
Join Date: Apr 2010
Posts: 538
Mein Auto: 760Li, F250 V10, Ex 7.3L
760Li, 135K miles. Anyone know the fuel pressure readings?

Does anyone know what static fuel pressure should be after several hours of sitting on the N73 engine?

I have recently replaced the in-tank fuel pump, and the main fuel filter with the FPR in it, that is under the car and behind the front wheel. They did not fix my issue.

Using DIS, to try to diagnose my long crank times after leaving the car sitting for hours, I am measuring the DME and DME bank2 fuel pressure sensors.

I know my residual cranking fuel pressure must be low (or I would probably not have this issue) and I am probably in for replacing both HPFPs, but they are not currently sending a code, besides an occasional (and not always reproducible) error 290F High Pressure sensor test / Short circuit to positive. It could be that there is no feedback loop to code if you lose cranking fuel pressure.

In the morning after 10-12 hours of sitting:

DME1 Rail pressure actual: 0.8 MPa (that's 116 psi)
DME2 Rail pressure actual: 0.2 bar (2.9 psi--dang, that is low)

Right after starting and idling: (I assume this is healthy, having nothing to go on)

DME1 Rail pressure actual: 3.0 MPa (that's 435 psi)
DME2 Rail pressure actual: 3.0 bar (43 psi)

measuring right after stopping engine

DME1 Rail pressure actual: 1.5 MPa (that's 217 psi)
DME2 Rail pressure actual: 0.9 bar (13 psi)


other errors I cleared last night, after a very dicey drive home were:

2721 Oxygen sensor aging behind converter
278C IAT shorting to positive
2783 MAF
274E misfire detection

heres' the thing: I drove to work today and had a fairly smooth ride and did not reproduce any of those errors, even after long cranking. You would think if these sensors were horked, they would code again, and probably immediately.
Reply With Quote
Ads by Google
  #2  
Old 02-12-2013, 03:44 PM
csmeance's Avatar
csmeance csmeance is offline
Officially Welcomed to the 'Fest
Location: Daytona Beach
 
Join Date: Dec 2007
Posts: 4,253
Mein Auto: 760Li
it sounds like your bank 2 rail is leaking pressure back after the car is turned off. Another member had a similar issue (760 owner as well) and they found that it was leaking into some sort of area in the engine where it should be dry. I'll try to rattle my brain and remember the exact member or where it was leaking into.
Reply With Quote
  #3  
Old 02-12-2013, 04:10 PM
mws mws is offline
Officially Welcomed to the 'Fest
Location: San Martin, california
 
Join Date: Apr 2010
Posts: 538
Mein Auto: 760Li, F250 V10, Ex 7.3L
here's the link

Quote:
Originally Posted by csmeance View Post
it sounds like your bank 2 rail is leaking pressure back after the car is turned off. Another member had a similar issue (760 owner as well) and they found that it was leaking into some sort of area in the engine where it should be dry. I'll try to rattle my brain and remember the exact member or where it was leaking into.
http://www.bimmerfest.com/forums/sho...=624365&page=2

yeah, I've seen this one. did not remember all the details. hey, duh, that's probably what the related persistent code for the fuel system is for.... 276D Tank venting system faulty

uhhhh.... reading my original post, I realize I left out that rather important little tidbit. ;-)

Last edited by mws; 02-12-2013 at 04:26 PM.
Reply With Quote
  #4  
Old 02-13-2013, 04:49 PM
mws mws is offline
Officially Welcomed to the 'Fest
Location: San Martin, california
 
Join Date: Apr 2010
Posts: 538
Mein Auto: 760Li, F250 V10, Ex 7.3L
check out my pics on this link

Quote:
Originally Posted by csmeance View Post
it sounds like your bank 2 rail is leaking pressure back after the car is turned off. Another member had a similar issue (760 owner as well) and they found that it was leaking into some sort of area in the engine where it should be dry. I'll try to rattle my brain and remember the exact member or where it was leaking into.
check the end of this thread, and my pics

http://www.bimmerfest.com/forums/sho...39#post7379739

thanks for the nudge csmeance. I had read that thread, but not made the connection. And I fear skuzlm3 is absolutely correct in all his assertions that you cannot have gas in there, without a failing HPFP vent diaphragm.
Reply With Quote
Reply

Bookmarks


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 7 Series / 8 Series > 7 Series - E65 / E66 (2002 - 2008)
Today's Posts Search
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On



Forum Jump


All times are GMT -7. The time now is 11:41 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms