Recently bought 97 MB E420 with 320K on the odo. Bought 8 new plugs, wires, and coil packs to replace, but can't find any good youtube videos or good images to study first. Does my Benz even HAVE wires? Are all these things REALLY contained under each valve cover (i can't see them anywhere else). Have done the 4 cabin filters, washer reservoir/pump, oil and filter and air filter change and found this car tougher than most to work on. Don't want to break anything.
97 Mercedes E420 Plugs, Wires, Coil Packs Rplcmt
- Thread starter Dada5
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You're going to want to track down a factory shop repair manual. Sometimes they can be found online or for sale on CD.
if they are like most german cars they are sitting under the plastic with a plug for each coil. just unplug and do them one at a time.
Dada5 Congrats on your new car. While 320k miles is a lot, the wires on these cars are usually replaced in singles as needed. Check the resistance of each wire- if one is in spec, keep using it, if out of spec, replace only that one wire(this is not chevy). If you replace all 16 wires, it will be quite pricey. I would strongly suggest and seriously consider buying the correct tool for removing each wire, it will make the job much easier. The wires usually cannot be removed by hand from any of the coils. It is available on line from Benz specialty parts houses. Otherwise you may damage the wires. If the sparkplugs look worn, then replace all 16 w/ correct replacements. This car may have a tool kit in the trunk with a vehicle specific plug tool. If plugs look OK, I would just drive the car and monitor the front sparkplugs on occasion. As others have mentioned, you MUST use anti-seize in the plug threads, no exception. You are wise to change the oil and air filters. The key to the twin filter air box is to line up everything precisely and it fits right in. Be sure to replace the oil drain-plug crush washer every time or it will leak(I have gained a number of Benz customers due to some shops not doing this). 5W-40 synthetic oil is what is usually recommended for your car. One more note, while this car specifies 8.5 QTS oil capacity, I have had many a late model Benz similar to yours show full adding 7.5 QTS or up to 9 QTS of oil- just do not overfill. The transmission uses a low viscosity synthetic fluid. I recommend to my customers the OEM MB synthetic fluid or the Amsoil Signature Series low viscosity ATF (assuming yours is an automatic). Just do a drain and fill & filter with such a high mileage transmission. If these cars are given strict excellent maintenance, they tend to last a long time. Good luck with this car and may it go another 320k.
Hi all. Thanks for all your input. I just went out and changed the plugs and coil packs. Nowhere did i see any traditional spark plug wires. Unless they are not under the valve covers where the coil packs are, it looks like it doesn't have them. Can ANYONE please confirm this, or is there somewhere else i should look?
If I remember correctly that motor would not have plug wires, plug wires would be on a pre 1995 M119 V8 when they had a coil ignition set up. After 1995 they went to a waste spark setup.
All you have to do is change the plugs, coils are about $100 each and are not changed unless they fail.
http://www.pelicanparts.com/techarticles...Replacement.htm
Here is an M104, which is similar, and an older M119.
Typically on Mercedes engines with plug wires you don't change them unless they fail, they are very high quality and proper OE replacement sets are very expensive.
All you have to do is change the plugs, coils are about $100 each and are not changed unless they fail.
http://www.pelicanparts.com/techarticles...Replacement.htm
Here is an M104, which is similar, and an older M119.
Typically on Mercedes engines with plug wires you don't change them unless they fail, they are very high quality and proper OE replacement sets are very expensive.
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