Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 01-26-2009, 07:01 PM
Registered User
Join Date: Jan 2009
Posts: 5
560sel won't start unless I pull the fuel pump relay?

Hi, I've been tracking down various problems with the fuel system and I think it's almost figured out. I replaced the fuel distributor with a spare and am getting pressure to it, and the piston is not stuck. Everything seems to be normal, and I adjusted the mixture screw so it should at least start. When I try to start it, it runs very rough on maybe 4 cylinders or won't start at all, but if I pull the fuel pump relay out it will start and run perfectly for a few seconds.. Could this be a fpr issue? I don't know what else to check, any help is greatly appreciated.
Reply With Quote
Old 01-27-2009, 09:09 AM
Join Date: Mar 1999
Location: Tucker, Ga USA
Posts: 12,153
Fuel pressure too high??? possibly the return is blocked OR regulator not allowing pressure to hold 100psi?

Try removing the return line from the A/C line.
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator
Reply With Quote
Old 01-28-2009, 06:54 PM
Registered User
Join Date: Jan 2009
Posts: 5
Thanks for the reply. I tried that, no change. I guess the next step is to get a fuel pressure gauge to check the regulator. Any ideas on a good one?
Reply With Quote
Old 01-30-2009, 11:18 AM
david s poole
Join Date: Mar 2005
Location: dallas
Posts: 1,822
if the car runs fine for a few secs after you pull the fuel pump relay i would guess that you have the mixture set very check pull fuel relay and jump terminals 87&30.this will run pumps with no ignition on.if you are rich you should be able to hear fuel from injectors[high pitched whine].back off [counterclockwise]adjustment on 3mm until noise just stops.then replace relay and start car.if you hear no noise then go the opposite[clockwise] until just before you hear the noise.this gives you a good starting point from which to adjust your fuel setting.
David S Poole
European Performance
Dallas, TX

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
Reply With Quote
Old 02-11-2009, 08:52 PM
Registered User
Join Date: Jan 2009
Posts: 5
Thanks for the idea, it worked. Got the car started, need to get a multimeter to check the duty cycle. It's doing something weird though, if I go around a turn and step on the gas the car stalls. It starts back up after cranking it for ~10 seconds, it's like the fuel is really low or something but there's plenty of gas in the tank. Anybody have any ideas? I miss driving
Reply With Quote


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
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 03:55 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page