xlr8tin

This morning while entering the interstate, I stepped on the gas pretty hard to get by a few cars. When doing so after a few second, the check engine light came on and started blinking. The car started to shake when I tried to continue to accelerate.

Also it wouldn't accelerate when the foot was on the gas. When coming to a stop a little later, the car would shake as if it were going to stall.

I finally pulled into a parking lot to shut off the car and reset the ECU. It seemed to work. The car seems to be shifting normally right now, but I haven't had it on a highway yet to test it. (kinda fraid to)

I later took it to Auto Zone, just to see the that code was saying. It said cylinder 5 & 7 had misfired.

Like I said it seems to be fine now, but can anyone tell me if I have a bigger problem on my hands or could this be a one time thing?

This isn't the first time I've accelerated this way. Also I've reset the ECU a couple times already this week due to sluggish performance, but everything seemed fine after.

Gregg

4runner

Same thing happened to me in my W210 E420 2 weeks back. Autozone confirmed misfire in cylinder 6. Since the spark plugs were just replaced it really narrowed it down for me. I pulled the coil on cyliner 6 and placed on another cylinder and the problem occurred on the cylinder I placed the bad coil on. Found one for $68 plus I went ahead and bought the spark plug tube for $11. Replaced and problem solved...good luck.

xlr8tin

Yeah, I've replaced my plugs less the 5000 miles ago.

Can you tell me where to find these parts and the name of the parts so I know exactly what I need to get?

Howellja

I assume you changed the wires when you did the plugs but if you didnt start with new wires or minimally a plug wire for that cylinder, I think some websites sell individual wires. If the plug wires dont solve the problem then look into replacing the coil pack. If you dont want a new coil pack from MB then try http://www.mbpartsonline.com/. They are a great site for everything from trim pieces for any benz and all guaranteed used parts.

xlr8tin

No, I haven't changed the plugs. I didn't feel like spending $250 for plugs, $250 for wires and the labor to put them in. But I may have to.

Not to say it won't happen again, but it is running fine right...I just need to get to the bottom of the problem. Should I buy wires and coil packs just for these 2 cylinders? Or am I going overboard?

Thanks for the website btw

Howellja

Buy a whole wire set and replace the tired wires. You probably can do the wires yourself, plugs are the harder part.

xlr8tin

I probably should replace those. I kinda wanted an updated suspension first, but that's life.

I actually bought two coil packs over the weekend on ebay for $55 each. They are mercedes parts...I talked to the person. Anyhow hope this all works.

Also the check engine light turned off by itself.

amgdriven

Man, IK16 plugs (Denso) and Magnacore 8.5 wires. I felt a difference with them. In fact, so has half of this forum who has also used the same plugs and wires. You can't go wrong.

Well worth the $500.00........and you can do it yourself. You need a cold engine, 2 hours of your time and swivel spark plug socket and extension. Trust me, it's not hard at all to do.

Howellja

Im sure the plug wires will do it, and if so just relist the coil packs or hold onto them if you plan on keeping the car for a while.

MaxVon

Hey Gregg,

Did you ever find the cause or solution?
I've got codes P0300, P0305,P0306 and P0307. My Mercedes tech fears it's the catalytic convertor ($2500!) because all misfires are on the same side of the engine.
I've got a 2000 E55 with 70K that has the original plugs and wires. I'm tempted to replace those first and see where it goes.

ruBENZ

Catalytic converter aside, you're due a tuneup...at least plugs. I would begin there. Good luck. :thumbsup:

MaxVon

Guilty as charged. I've just recently moved back to New England (ya, I know WTF was I thinking!) and have put off some things due to moving expenses. I'll see if I can find a buddy here to lend me a bay at his shop so I can do the plugs tomorrow.
I've seen a number of posts on this "misfire" subject on this forum and others but only a handful of solutions.
Thanks for the advise.
Max

xlr8tin

MaxVon,

I haven't had any problems since I replaced the two ignition coils. As ruBENZ mentioned, tune up would be a wise thing to do. I know have 111K miles, and no problems with all new plugs and wires...and the two new ignition coils.

Kinda funny...I just moved away from New England...Good luck. The timing sucks this time of year.

But if you are having misfires like I experienced..start with the wires and plugs, and than the coils.

MaxVon

Last Friday I changed the plugs and wires and still the same codes and behavior. I have a friend who is an advisor at a MB dealer who put me in a new C280 loaner on Saturday and had his best tech diagnose it as indeed a bad catalytic converter. Unfortunately my E55 is 3 months out of the 8 year/ 80K warranty for emissions related probelms. I started investigating aftermarket converters and custom muffler shops and got quotes for around $500~$600 to fabricate a fix. Really not happy about the whole situation. Then the phone rings on Monday....Mercedes-Benz is going to "Goodwill" my converter and the labor!!!. I picked up the car today and all I can say is WOW! It has never performed like this before. Previously it felt like an E430 but now it's a totally different animal! I cannot believe MB did this. I guess it pays to have a friend in the business. Thanks to all for the advise and responses.
Best regards,
Max

Mfte55black

I have a general tip for each of you.....I have found that using Chevron Premium fuel and adding a bottle of Chevron's 'Techron Fuel System Cleaner' once per month has kept my engine running extremely smooth this past year. While the problem in this thread was ultimately determined to be a 'catalytic convertor' issue...its good for all of you E55 owners out there to know I have had tremendous success using Chevron gas and an occasional bottle of their Techron additive in my gas tank...

The local Mercedes dealership where I service my car said my car's spark plugs and fuel injectors were in 'excellent shape'...(it has 75k miles on them)

I didn't mention the use of Techron to the service manager at Mercedes....but I believe it has something to do with the condition of my engine's combustion chamber. Friends riding in my car often think the engine is not even running....its that smooth!

(and no folks....I do not work for Chevron!)