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 06-25-2019, 09:53 AM
Registered User
Join Date: Jul 2014
Posts: 196
M102 / 103 random engine tapping / knocking - video inside

Hi All,

85 230E with an M102 from an early model 190E 2.3

Healthy, normal quiet engine with ample oil changes and correct oil level.

About two months ago the fuel pump began failing causing the vehicle to starve of fuel when climbing hills. Car was limped home over the corse of an hour or about 40 miles.

Replaced the fuel pump and all other items in the back of the vehicle last night and went to start it up. Fired right up but immediately the engine began making a VERY loud tapping / knocking sound at idle and when revving.

Once the engine warmed up a little the sound diminished at idle but comes back when revving.

I pulled each of the spark plugs one at a time and the sound does not change.

I tried loading the engine (lugging it) while driving and it does not change.

Could this be a noisy valve system component or something worse?
Prior to the fuel pump issue this engine ran very quiet and nearly flawless.

Link to video :
Reply With Quote
Old 06-26-2019, 08:56 AM
optimusprime's Avatar
Trevor Hadlington
Join Date: May 2014
Location: Worcestershire in England
Posts: 1,206
I would remove the valve cover start it and observe the valve operation..
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 08:44 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, 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