algevor58

is anyone have some pictures how to change spark plugs on 1997 s500

hcetzneb

Remove the black covers on top of the valve covers E10 tork.. Under there are your coils remove them and then your plugs.... Try the plugs first but those engines it was very common to get bad coils

tomsantos

Just had S420 shake and idled roughly. Brought it to my independent MB repair shopand told me misfire on 1 and 6 cylinders. I was afraid the pistons/cylinder head blew but was informed car needed coils on both cylinders replaced. Also vacuum hoses have to be replaced. I should have checked vacuum hoses first. This could have been the culprit. Cost? $700.00 parts and labor. Recommende spark plugs replacement for $350.00. I declined since I can replace them myself. hope this helps.

mikeyle

ive had this problem so many times i cant even begin, initially ignition coil 1 misfired, then 8, then 7, then 2, then 6, and then 3. this all happened over the course of 20k miles, i have a 97 s420 with around 140k miles now. dealership cost for replacement was around 400 a coil, my indy shop is around 200.

Drjones217

Mine shakes when I first take off, then it smooths out at around 40 or 50 miles an hour. Don't know if it's coming from the engine or the front end. Anyone have that problem before?

tomsantos

The first time it happened, i thought the car S420 '97 was having vacuum issues. Brought it to my indie MB shop. I was told, 2 cylinders are misfiring and 2 coils were bad. Had it fixed. Cost me more the $500.00. After 8 mos., it happened again. This time, I decided to do it myself. It was easy. Remove the air intake cover to expose the 2 banks of cylinders. Remove coil covers to expose all coils/ plugs. Torx and Allens will be needed. You will easily distinguish the original (old) and replaced(new) coils. Loosen 2 screws holding the coil bracket on each of the suspect cylinders. Start the engine. With the engine running, gently lift the coil and observe if there is a change in the engine speed. If the engine gets more rough, push the coil back into the spark plug. Proceed until you get to the coil/s where you will not notice any change. This/these will be the culprit/s. I found 2 bad coils and since 5 have already been replaced, I ordered 3 coils from Autohaus and replaced the remaining 3. Saved me several hundreds of $$ and my car is purring like a cat and loves its acceleration. BTW, I replaced all 8 plugs w/ Bosch 4+. I hope this helps and save you money.

Wyverne

I am having something of a problem with that myself, my car is something of a scrap metal intervention, it was going to be on a tow truck to the shredder if I hadn't spoken up and "saved" it, it cost me a hundred seventy five dollars and a cute little original edition Suzuki swift,
I drag it home on a trailer, a stipulation on the sale was that the car "does not run", I do believe as I was told that, somewhat emphatically, there should have been exclamation points, as someone who has been a mechanic on clunky junky cars for a very long time, you learn how to fix what breaks, and one day there came an opportunity to actually get a first edition w140, 99.44 percent intact, original.

Maybe it is some sort of macabre forensic mechanical examination process that has happened, or this car is so mechanically refined it may actually be possessed, any number of possibilities come to mind.

A visit to a number of junkyards found a lot of parts, fuel pumps, fuel lines, blower motor and regulator, trim parts, cigarette lighters, fuel cap.
An adventure in automotive restoration has begun, in three months, I have spent about sixty dollars for parts, all the vehicle is there, it has layers of dirt, grease and needs a thorough going over through and around.

For Mercedes Benz to actually spend a Billion dollars on this model vehicle in the development stage, wow! It sure must have been something fantastic that they envisioned it to be as the final product.

I am doing a forensically correct rebuild of my car, there are very few machines that can duplicate the performance characteristics of a w140, sure, they were built with some built in parts that were not quite up to the expectations, over time, the problems show themselves, a very powerful and amazing automobile, in its time, even to this day.


for the past few weeks I have been having a couple of cylinders that have a really weak spark, the engine has at least two cylinders that scarcely fire at all, I cleaned out a layer of green corrosion from under the distributor caps, using fine sandpaper to shine the contacts, I found one of the primary coil wires pinched under the air conditioner condenser tank, from the factory assembly, the spark at the distributor cap is nothing short of portable lightning once I got that untangled, Wow!


I am going to try and find out if the spark plug wires are bad, or if the problem is in the distributor caps, there is a black plastic cover over the orange color distributor cap that I cannot figure out how to remove without breaking it, the oil and grease and arcing and sparking happened as I was trying to go through the firing order trying to find the "miss" in the engine, by disconnecting one spark plug wire at a time, there seemed to be a lot going on under the plastic cover.


I do not yet know where the source is for the ignition coils to receive their information from, but it appears that this missing spark iis a common problem for many of these vehicles.
I will be following this thread to see what we can find out.

khan888

Please tell me when your problem is resolved . And and aslo tell me how you did ?

Thanks we are really loving our tank

oldsinner111

On my car I replace them every 150,000 miles,all of them

mercw140

hi
I have the same problem with my s500. Its the centre bearing on the drive shaft.
Would recommend replacing the bearing and have the drive shaft re-balanced.

rosswell

Well it's now happened to me - missing on at least 1 cylinder but feels like 2.

Drove it home thinking about new plugs, wires, coil packs. With only 70,000 kms and from what i've read on here- I think probably it's a good idea to replace the lot and do it once... (the shaking at stop lights, the underpowered run down the highway - just started it doing it for first time ever on a day that's +10 C and saw the engine running at temperature down the highway.

Notably the shop would have likely had the covers off recently in December when they did some gasket work for me - wonder if they wiggled something or if it wasn't put back - I"ll check under my black plastic cap..... Any other thoughts?

burgca

Depends on year of the car as it could be a bad coil or distributor and wire. The engine change over was the 96 model year from Distributors wires to coil.
http://www.peachparts.com/shopforum/...n-systems.html

rosswell

MB dealer service fixed me up for $700 with new plugs, plug wires to coil, (ignition coil extenders). Runs like a top now!