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 02-22-2017, 12:43 PM
Registered User
Join Date: Feb 2016
Posts: 43
Motor mounts diy and oil pressure low at idle m103

190e 2.6, in idle the oil pressure drops to around .3 to around .7 bar , it rises all the way when driving. I'm assuming there's a vac leak somewhere because the economy gauge is around 1/3 to the right from the peg. Or could it be my icv and the associated hoses, had some whack job try and adjust to lower my rpms ? Also if I need to replace my motor mounts how can I do the driver side ? I have all new and correct ignition parts from the distributior and new injectors plus the seals for it as well. New fuel filter. Car drives pretty good except for some gear changes being sloppy ( modulator ?) No misfires or stumbling now, hard starts are non existent also with the new injectors. Before I put the new injectors I had an Indy adjust the duty cycle do I need this readjusted because of the new injectors ?
I've attached some pictures to describe the low oil pressure on drive at idle stuck in traffic,( it gradually drops the longer I'm idle in traffic)

Reply With Quote
Old 02-22-2017, 12:52 PM
Registered User
Join Date: Feb 2016
Posts: 43

All these are idling in traffic the bottom is just when I hit traffic and top is after 20 mins
Reply With Quote
Old 02-22-2017, 02:10 PM
Registered User
Join Date: Jan 2009
Posts: 146
I really struggled with the driver's side mm. What I finally ended up doing is taking apart the throttle linkage and using a long 3/8 extension through the manifold after placing the socket on the mm top nut and plugging the extension into the nut. Must be a better way, but this worked for me. BTW, my oil pressure went zero @ idle. It was the sender.
Reply With Quote
Old 02-22-2017, 04:37 PM
Hit Man X's Avatar
Join Date: Sep 2004
Posts: 9,087
Thumbs up

Is this your first vehicle with an oil pressure gauge? What about a vacuum gauge?

Vac is lower in gear than in neutral/park conditions. The thing pulls maybe 17" fully sealed, I would imagine you are seeing 12-14" tops under load.

Oil pressure drops to what you are seeing when the vehicle and oil are up to temps. On my M103 cars, even with OE spec 20W50 I see sub 1 bar (but more than 0 bar obviously) pressures at idle when fully hot. As soon as I am back on the throttle, it jumps up.

I believe I read idle speed for a hot M103 in park/neutral is around 700rpm and drops to about 540rpm in gear. I could look it up if you care.
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.
Reply With Quote
Old 02-22-2017, 08:06 PM
gatorblue92's Avatar
Save the manuals!
Join Date: Jan 2006
Location: Delaware
Posts: 3,393
Both M103 powered cars I have owned showed the same oil pressure at idle. As long as it pegs once you give it some throttle I wouldn't worry.
1977 MB 240D 4 speed 145K - Nearly Perfect
1995 MB E420 197K - Weekend Toy
2018 Ford F150 5.slow 23K - My DD
2020 Subaru Ascent 10k - Wife's DD

1979 MB 280E 90K - Sold
1983 MB 240D 238K - Scrapped
1984 MB 300D 347K? - Sold
1984 MB 300TD Wagon - 188k - Sold
1987 MB 300E 5 speed 258K - Scrapped
1991 MB 300TE 5 speed 276K - Sold
1993 MB 400E 218K - Sold
1993 MB 400E 130K - Sold
1995 MB E320 Wagon 190k - Sold
Reply With Quote
Old 02-23-2017, 06:44 AM
optimusprime's Avatar
Trevor Hadlington
Join Date: May 2014
Location: Worcestershire in England
Posts: 1,339
Should be up near to the top stop at start up .And the thing is , as long as you have pressure like one digit on the guage at tick over its ok .But check the oil pressure sender they have been known to leak from the base , so then you will end up with a low oil pressure.
Reply With Quote
Old 02-27-2017, 05:33 PM
Registered User
Join Date: Feb 2016
Posts: 43
Those pics were from pretty cold days, today in toronto it was pretty warm out and the vacuum gauge was pretty close to the peg and the oil pressure was holding steady at 1 with momentary drops when downshifting to a stop.
Reply With Quote
Old 03-02-2017, 02:21 AM
lsmalley's Avatar
Registered User
Join Date: Oct 2006
Location: California
Posts: 1,988
Everything seems fine. Leave it alone if its running fine now because you'll be so pissed when you develop a rough idle or hard start that will take you months to figure out. motor mounts are easy. remove the fuel distributor and it will take you maybe an hour or less


1990 190E 2.6L
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 05:08 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, 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