Hi all, thanks for reading, & I'll state right off I'm not the most "mechanically knowledgeable" person , so I apologize if this is in the wrong section. I have a question & am seeking advice both for a solution & to get an idea if the guy I took my car to is "on the up and up." A few days ago, my 1987 190E 2.3's engine started to shake severely. (is at worst when driving at low speeds or idling) Other "symptons" also include a significant loss of power (barely makes it up steep hills) and sluggish acceleration in general. Thinking it might have to do with the spark plugs, I took it to the place where I had them changed a few months back. They inspected the plugs, discovering oil on one of them. He then told me that as a result, I was only running on only 3 cylinders and basically had 3 options; replace the engine, rebuild the engine, or he could do some kind of temporary fix he called "an extension" (for the cylinder that leaked oil onto the plug). Has anyone had any of these problems &/or have an opinion about the diagnosis I was given? Thanks in advance for any replies!

 

Hi,
All depends on "how oily and why" AND
Do you use oil?
Do you trail blue smoke?

The engine cylinder has obviously NOT been running correctly and this is the cause of the poor performance and shaking.
Question is why!

It COULD be a simple as that cylinder has not been firing becuase of an ignition problem (no spark) or a badly faulty injector etc....HOWEVER
it could be a damaged piston, piston ring, broken valve etc ....

IN WHICH CASE the diagnosis is correct. (I have no idea what the extension alternative is).

MY NEXT MOVE would be to determine what the compression pressure is on each cylinder.
They should ALL be of similar value AND
should also be around the normal pressure for this sort of test.

This will decide if it is an external or internal problem to the cylinder.

Stuart.

 

a 190 2.3 should have a m103 engine inline 6cyl. which was notorious for leaking valve guide seals what happens is that overtime the valve guides wear and the valve start rock side/side in bore widening up valve stem seals causing oil to leak past down guide overvalve to top of piston then start to foul out spark plug so you have rough idle , loss of power then hard start to no start te repair is 2 ways right way and fix it cheeply so i get more usage before i have to pay. #1 (costly!) rebuild top cyl. head valve job and replace valve guides with brass ones the mb dealer parts dept. knowns exactly what you need . then since your car is cis(mechanical injection) there is updated fuel injectors i believe there brass as well if
this has not been done it should be explain some driviablity issues . so parts are head set ,injectors, headgasket , then a shop to cut the valve seats and valves if live in s. cal i recommend motor works in san dieago just send them the head theyll do the rest and reasonable #2. (buys time only ) valve stem seal replacement need valve covergasket set , valve stem seals , any other parts which you might break , and a over head spring compressor which is bought at any autostore around $25 ,cylinder leak detector and a air compressor to charge the cyl. with air . what you do is put one of the cyl . on top dead center compression (tdc) remove spark plug install leakage gause and hose place 90psi in cyl with overhand spring compressor (ohsc) place over valve spring compress with a magnet remove spring keepers DONT LOOSE THEM!!! slowly release spring and remove MAKE SURE VALVE DONT FALL INTO CYLINDER OR HEADS COMMING OFF !!! replace valve stem seal reinstall do that all the way down the row replace spark plugs drive should have no more miss fire for a while usually 20k or so
NOW! NO ON EXTENSIONS!!! they dont do anything all its a threaded extension which screws into the head and the spark plug screw into that suppose to keep oil off electrode you can buy them any autoparts store my opinion they suck !!!! well good luck