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123 126 diesel vacuum leak diagnosis

Submitted by andycox@twcdc.com on 19 June 2008 - 7:02am.
My 1985 300TD has a vacuum leak. The engine won't shut down without using the manual stop and the door locks don't work. The brakes and transmission are working fine. Does the fact that the brakes and transmission are working while the shutdown and doors are not, help in locating the leak? Or, do I follow all the usual steps (as described in Kent's vacuum source leak detection manual)? [by the way, is it possible to search the forums?]
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I would just follow Kent's

19 June 2008 - 9:01am
CMPeterson
I would just follow Kent's "Vacuum Diagnosis" book. As for searching forums...No I do not think you can, although it would be a GREAT addition in my opinion. Chris

1984 SD300 power brakes erratic operation

30 June 2008 - 4:28pm
glenne1949
power brakes operate eratic, at times as if no power assist. Something loose in rear end power train eventually engages where with heavy pressure on brake pedal allows brakes to stop vehicle. Does this indicate loss of vacuum?

Yes it does

2 July 2008 - 2:12pm
Kent Bergsma
You could have a leak in your brake booster, a problem with your vaccum pump, or a leak elsewhere that could be pulling vacuum away from the booster. Any of these will lead to the symptoms you describe. For troubleshooting tips see my Vacuum Source Troubleshooting manual