Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 07-11-2000, 12:47 AM
Posts: n/a
Could anyone give me some suggestions about my tachometer on my 83 300D which i just bought. Most of the time it dosent work, or it may work sometimes esp. if left at idle for a while. Sometimes the needle jumps around. Where should i start? Replacing the gauge or is it something else?
Reply With Quote
Old 07-11-2000, 12:57 AM
Larry Delor's Avatar
What, Me Worry?
Join Date: Jun 1999
Location: Sarasota, Fl.
Posts: 3,028
Do a search on it you will find lots of info on this little gremlin. (search link towards top right)
Reply With Quote
Old 07-11-2000, 08:21 AM
Join Date: Mar 2000
Location: Gainesville FL
Posts: 6,844
The tach works off an rpm sensor on the front of the motor. The sensor very seldom goes bad. The AC signal generated by the sensor is interpreted and converted to a pulsed DC signal by a transducer screwed into the diagnostic port on the left fender. This is almost allways the problem and isn't very fixable without replacement as the electronics are sealed in plastic (molded in plastic).

The pulsed signal goes to the tach which is fairly trouble free. From fixing many bad ones I can verify their failures though. The failures are almost always the capacitors in the tach circuitry.
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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
87 300D vs 300D 2.5 Turbo... speedy300Dturbo Diesel Discussion 31 02-09-2005 11:29 AM
Get that 300D Turbo out of left field! KeithG Diesel Discussion 22 01-06-2003 01:26 AM
87 300d turbo cowboy Diesel Discussion 6 12-13-2002 03:07 PM
Veg oil in 300D turbo Fredmburgess Diesel Discussion 43 11-21-2002 09:53 AM
85 300D turbo shoe Diesel Discussion 4 11-14-2001 09:32 AM

All times are GMT -4. The time now is 01:26 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page