Volvo Community Forum. The Forums of the Volvo Owners Club

Forum Rules Volvo Owners Club About VOC Volvo Gallery Links Volvo History Volvo Press
Go Back   Volvo Owners Club Forum > "Technical Topics" > S80 '98-'06 / S60 '00-'09 / V70 & XC70 '00-'07 General

Notices

S80 '98-'06 / S60 '00-'09 / V70 & XC70 '00-'07 General Forum for the P2-platform S60 / V70 / XC70 / S80 models

Information
  • VOC Members: There is no login facility using your VOC membership number or the details from page 3 of the club magazine. You need to register in the normal way
  • AOL Customers: Make sure you check the 'Remember me' check box otherwise the AOL system may log you out during the session. This is a known issue with AOL.
  • AOL, Yahoo and Plus.net users. Forum owners such as us are finding that AOL, Yahoo and Plus.net are blocking a lot of email generated from forums. This may mean your registration activation and other emails will not get to you, or they may appear in your spam mailbox

Thread Informations

v70 2.4 T5 Fuel pressure 2004

Views : 551

Replies : 7

Users Viewing This Thread :  

Reply
 
Thread Tools Display Modes
Old Nov 29th, 2020, 18:16   #1
richcourt
New Member
 

Last Online: Dec 1st, 2020 07:53
Join Date: Sep 2020
Location: shepton mallet
Default v70 2.4 T5 Fuel pressure 2004

have a 2004 T5 2.4 that has recently developed a fuel pressue issue. On start up using a pressure guage it runs at 43 psi and then after approx 5 minutes the pressure starts to drop and a couple of minutes later the car stalls. Turning the ignition off and back on the pressure goes back to 43 psi and starts instantly. Have replaced the pcm, fuel pressure sensor, fuel filter and pump. So can anyone tell me what the voltages should be at the pressure sensor - 4 wires please!!!
richcourt is offline   Reply With Quote
Old Nov 29th, 2020, 21:53   #2
Clan
Experienced Member
 
Clan's Avatar
 

Last Online: Today 14:09
Join Date: Jun 2007
Location: L/H side
Default

Quote:
Originally Posted by richcourt View Post
have a 2004 T5 2.4 that has recently developed a fuel pressue issue. On start up using a pressure guage it runs at 43 psi and then after approx 5 minutes the pressure starts to drop and a couple of minutes later the car stalls. Turning the ignition off and back on the pressure goes back to 43 psi and starts instantly. Have replaced the pcm, fuel pressure sensor, fuel filter and pump. So can anyone tell me what the voltages should be at the pressure sensor - 4 wires please!!!
voltage increased with pressure ,
should be 1.8v to 2 v at the operating pressure of 350 - 400 kpa ( absolute pressure ) on pin A2 of the ECM

there is a pin A 3 which is fuel temperature
__________________
My comments are only based on my opinions and vast experience .
Clan is offline   Reply With Quote
Old Nov 30th, 2020, 01:41   #3
oragex
Premier Member
 
oragex's Avatar
 

Last Online: Jul 26th, 2021 22:24
Join Date: Jun 2013
Location: Coldnada
Default

A 2004 ? Read about CEM corrosion, may look from under the dash with a flash light for dry or wet traces of water
__________________
Several Volvo Repair Videos https://www.youtube.com/playlist?lis...ECTts0FSVSOT_c
oragex is offline   Reply With Quote
Old Nov 30th, 2020, 19:10   #4
richcourt
New Member
 

Last Online: Dec 1st, 2020 07:53
Join Date: Sep 2020
Location: shepton mallet
Default

Quote:
Originally Posted by Clan View Post
voltage increased with pressure ,
should be 1.8v to 2 v at the operating pressure of 350 - 400 kpa ( absolute pressure ) on pin A2 of the ECM

there is a pin A 3 which is fuel temperature
amazing - thank you so my issue is as the fuel pressure starts falling the voltage drops - i can't work out if it the voltage dropping off or the pressure dropping causing the voltage to drop - that makes sense in my my head!!!
richcourt is offline   Reply With Quote
Old Nov 30th, 2020, 19:12   #5
richcourt
New Member
 

Last Online: Dec 1st, 2020 07:53
Join Date: Sep 2020
Location: shepton mallet
Default

Quote:
Originally Posted by oragex View Post
A 2004 ? Read about CEM corrosion, may look from under the dash with a flash light for dry or wet traces of water
thank you for your reply - would a faulty CEM affect the running - probably a stupid question but not very conversant with volvos!!!
richcourt is offline   Reply With Quote
Old Nov 30th, 2020, 23:04   #6
Clan
Experienced Member
 
Clan's Avatar
 

Last Online: Today 14:09
Join Date: Jun 2007
Location: L/H side
Default

Quote:
Originally Posted by richcourt View Post
amazing - thank you so my issue is as the fuel pressure starts falling the voltage drops - i can't work out if it the voltage dropping off or the pressure dropping causing the voltage to drop - that makes sense in my my head!!!
have you measured the voltage when the engine is running and watched it fall as the engine splutters to a stop ? if the pressure sensor output drops The PEM should increase the pump speed to maintain the pressure again .

No there is nothing in the CEM which affects the Engine calibration , that's all in the ECU .
__________________
My comments are only based on my opinions and vast experience .
Clan is offline   Reply With Quote
Old Dec 1st, 2020, 07:53   #7
richcourt
New Member
 

Last Online: Dec 1st, 2020 07:53
Join Date: Sep 2020
Location: shepton mallet
Default

yes, as the pressure drops the voltage drops slowly until the engine dies and then shows 0.8v turn ignition off and recycle twice and the voltage goes back to 2.4v and pressure goes straight back to 43 psi so Im thinking i might have bought a faulty pressure sensor or i have a wiring fault. Have tried two different PEMS off running cars
richcourt is offline   Reply With Quote
Old Dec 1st, 2020, 11:52   #8
Clan
Experienced Member
 
Clan's Avatar
 

Last Online: Today 14:09
Join Date: Jun 2007
Location: L/H side
Default

Quote:
Originally Posted by richcourt View Post
yes, as the pressure drops the voltage drops slowly until the engine dies and then shows 0.8v turn ignition off and recycle twice and the voltage goes back to 2.4v and pressure goes straight back to 43 psi so Im thinking i might have bought a faulty pressure sensor or i have a wiring fault. Have tried two different PEMS off running cars
as soon as the voltage drops the PEM should be speeding up the pump to bring the voltage back up have you tried applying 12v direct to the pump and seeing what is pressure available ? I believe there is still a mechanical fuel pressure regulator in the lines at the rear which may be leaking fuel back to the talk?.
__________________
My comments are only based on my opinions and vast experience .
Clan is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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 Off

Forum Jump


All times are GMT +1. The time now is 18:05.


Powered by vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.