1993 300SD no vacuum issue

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1993 300SD no vacuum issue

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1993 300SD no vacuum issue - 1/27/2008 8:37:42 PM

todds300SD

Posts: 2
Joined: 1/27/2008
Status: offline

Hello to everyone, what a great site... As a newbie here I have a question about my 1993 300 SD. My turbo waste gate is not working lack of power... checked the vacuum line to waste gate actuator nothing... Back tracked to vacuum pump on engine, have vacuum... the problem starts with no vacuum on the out source side of the right vacuum transducer behind the passenger headlight. My car has two of these things. What does the vacuum transducer do and might this solve my wastegate problem ?? If anyone knows what these thing cost and any test that can be done to see if the transducer is working would be great. Also below the transducer there is a switch or a relay of some kind that the vacuum line for the wastegate comes out of what is this and what does it do? Thank you all in advance for your help here.... Todd

Post #: 1

RE: 1993 300SD no vacuum issue - 1/29/2008 10:00:45 AM

pvtauto

Posts: 3
Joined: 1/29/2008
Status: offline

HI TODD
ARE YOU SURE THAT YOUR BOOST PRESSURE LINE DOESNT JUST RUN FROM THE TURBINE HOUSING TO THE WASTEGATE CONTROL DIAPRAHGM ,I CANT RECALL SEEING ANY OF THESE SYSTEMS RUN THRU VACUUM THEY NORMALLY USE THE PRESSURE CREATED ON THE TURBINE SIDE TO CONTROL THE WASTEGATE MOVEMENT AND NORMALLY DO NOT HAVE ANY THING ELSE CONNECTED TO THEM .YOUR LACK OF POWER COULD BE CONTAMINATED FUEL , MALFUNCTIONING ALDL COMPENSATER ,INJECTOR PUMP ISSUES OR FUEL SUPPLY ISSUES

(in reply to todds300SD)

Post #: 2

RE: 1993 300SD no vacuum issue - 1/31/2008 8:39:20 PM

todds300SD

Posts: 2
Joined: 1/27/2008
Status: offline

dear PVTauto,

Thanks for the reply... I am almost certain that the wastegate is actuated by the vacuum transducer... I have the star manual and it seems that that is the case. Do you know if you can hear the turbo spool up on these cars ?? Maybe I need to check out the things you mentioned. I dont think it is bad fuel, replaced both filters, havent looked at the alda unit or the injection pump yet. was thinking that with no vacuum to wasteagate actuator it might be stuck open. ( thinking of opening up turbo and seeing if it is stuck or carboned up) might need a good cleaning.. Car has little low end power when starting off, after you hit around 40mph she seems to go strong.. Thank you so much for your help... And any other ideas would be great... I'll keep you updated... Seems like the 93 140 is not the most popular model around, but I sure love her lots.... have 210,000 mile on betty the benz...

(in reply to pvtauto)

Post #: 3

RE: 1993 300SD no vacuum issue - 6/22/2008 8:05:43 AM

martha_c

Posts: 5
Joined: 2/24/2007
Status: offline

Todds, did you ever get to the bottom of your problem. I''m having similar issue on my ''92 300SD., I love mine lots, too!

(in reply to todds300SD)

Post #: 4

RE: 1993 300SD no vacuum issue - 6/22/2008 7:56:55 PM

ForcedInduction

Posts: 858
Joined: 5/20/2006
From: Federal Heights, Colorado
Status: offline

The wastegate on the 90+ diesels are vacuum controlled.

_____________________________

1980 240D 3.0VNT 222K Miles. OM617.95, GT2256V VNT turbo, 4-speed manual, 3.46 diff, 15mm rear swaybar, ALDA removed, no EGR and Amsoil by-pass oil filter. Currently 107HP and 195lb/ft of torque at the wheels.

www.youtube.com/Turbo617

(in reply to martha_c)

Post #: 5