home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > maintenance & nonperformance

Reply
 
Thread Tools Display Modes
Old 07-29-2021, 10:22 PM   #1
autoloclys
Board Member
 
Join Date: Dec 2016
Location: Boston MA
Default uneven running, fuel pressure issue?

having an annoying issue but so far it hasnt left me stranded.

In normal driving on the road, the engine in my '92 240 will occasionally stumble a little, its most noticeable between 1500-2000 rpm. Idle is smooth and above 2000 rpm the stumble is either not there or not noticeable

both fuel pumps are new since i bought the car and seem to be running (i can hear them when i check), Fuel pressure regulator also seems fine, no fuel in the vacuum line. and all the fuel lines between the tank and the engine have been replaced, though the return line is hose and not hard pipe

is it possible the intank or under car fuel pumps are running but not supplying sufficient pressure for certain conditions? neither one is a volvo part, but i would expect them to work or not work, rather than lose pressure slowly or intermittently.

or am i totally up the wrong tree with the fuel system?
autoloclys is offline   Reply With Quote
Old 07-29-2021, 10:47 PM   #2
James M
Bored member
 
James M's Avatar
 
Join Date: May 2017
Location: Chico, CA
Default

.

Last edited by James M; 07-29-2021 at 11:22 PM..
James M is offline   Reply With Quote
Old 07-30-2021, 02:31 AM   #3
mattd1205
Board Member
 
mattd1205's Avatar
 
Join Date: Dec 2014
Location: Los Angeles, CA
Default

I’d check for codes first if you haven’t already. If you suspect a fuel pressure issue, throw the autozone rental fuel pressure gauge on there. It doesn’t come with the fittings you need but you can cut up a fuel rail and part of the fuel line from a junk Volvo at the junkyard to make an adapter that will plumb into the tee fitting that comes with the gauge kit.
mattd1205 is offline   Reply With Quote
Old 07-30-2021, 02:39 AM   #4
Otto Mattik
board member
 
Otto Mattik's Avatar
 
Join Date: Dec 2015
Location: Upper Midwest more or less
Default

Quote:
Originally Posted by autoloclys View Post
having an annoying issue but so far it hasnt left me stranded.

In normal driving on the road, the engine in my '92 240 will occasionally stumble a little, its most noticeable between 1500-2000 rpm. Idle is smooth and above 2000 rpm the stumble is either not there or not noticeable

both fuel pumps are new since i bought the car and seem to be running (i can hear them when i check), Fuel pressure regulator also seems fine, no fuel in the vacuum line. and all the fuel lines between the tank and the engine have been replaced, though the return line is hose and not hard pipe

is it possible the intank or under car fuel pumps are running but not supplying sufficient pressure for certain conditions? neither one is a volvo part, but i would expect them to work or not work, rather than lose pressure slowly or intermittently.

or am i totally up the wrong tree with the fuel system?
a) injector leak ?
b) fuel pump relay ? (what brand)
c) AMM resistance check out ?
__________________
Desperate need of elf assistant for interior work - Cash/Beer option $


Feedback thread: http://forums.turbobricks.com/showthread.php?t=323689

Last edited by Otto Mattik; 08-02-2021 at 03:03 AM..
Otto Mattik is offline   Reply With Quote
Old 07-31-2021, 07:15 AM   #5
Janspeed
Board Member
 
Join Date: Sep 2005
Default

d) throttle body axel wear? (causing intermittent vacume leak)

Last edited by Janspeed; 08-06-2021 at 04:25 PM..
Janspeed is offline   Reply With Quote
Reply

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 -4. The time now is 01:05 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.