learpot

Hi dear friends: About two years ago, I bought a used 2005 Mercedes-Benz S600 with 60,000 miles on it. Since I bought it, it started to have some strange misfire problems. I don't drive the car that often, maybe once per week. What happens is that, I drive a car for about 10 to 15 minutes to a place, And then I parked the car for maybe half an hour. When I start up the car again, I got this engine shaking and check engine light went up. When I press the gas pedal, I feel like I'm not having enough power. It feels like only half of the engine is working. And in this kind of situation,I wait 10 to 15 minutes, restart the car with same thing. I wait another 10 to 15 minutes and restart the car, the strange engine shaking and the loss of power goes away. And everything was back to normal I have a full power again.

Initially, I was thinking this might be the fuel system problem, maybe the fuel injectors are clogged up, so I got a mechanic to do a fuel treatment. However the fuel treatment messed up the fuel pump, so I have to replace the fuel pump and the fuel filter right away. I also replaced the battery by thinking maybe the battery is getting old and not able to generates enough voltage for the spark plugs. But problems continues. It almost happens exclusively when I left my car without driving it for 1-2 weeks. The engine code disappeared spontaneously after everything is back to normal.

Yesterday, the engine shaking and loss of power happened again. I then got an OBD reader to read the code. The code show misfire in cylinder 1,2,3,4,5,6.so today I talked to my mechanic, my mechanic suggest it might be the coil pack which is failing. I looked over on the Internet, I saw there's different answers. Some were mentioning worn spark plugs, clogged catalytic converter, bad Coil packs, oxygen sensor, wiring harness. My mechanic says he can do a diagnostic test, but he might not be able to catch the problem.

So I came here guys, what do you guys think? My thought process would be, if the coil packs are failing, it should cause one cylinder misfire instead of six. Also a misfire should happen mostly during driving rather than just starting the car. The car drives smooth otherwise. If I drive the car every day, there's no such problems. It only intermittently happens(5 times in past 2 years) when the car is left un-driven over 7 days or so. I'm thinking driving the car for 15 mins might drain an uncharged battery to make it insufficient for spark plugs, or when I parked the car first time something might got heat up by the engine on the passenger side to prevent proper firing for the right cool pack. I don't feel comfortable to replace the expensive coil pack without finding a real problem.

Please give me some advice, thank you so much guys.

Dan

ibeforreal

You could start by having a MB dealer or someone with a STAR Diagnostic system run test on the car before spending more money. There are lots of possibilities so it could be your Mass Air Flow Sensor (MAF), Crankshaft Position Sensor (CPS) or the coil pack and/or spark plugs.

drewk88

I don't think the S600 has a Mass Air Flow sensor.
I do not find one on my 2004 S600.

tusabes

The coil pack or transformer between the coil packs is most likely

Both does cause multiple cylinder misfire so half the engine goes dead not just one cylinder

Autozone and oreilly offer lifetime warranty on coil pack if you buy through them and it's the same part

kraut56

Never change parts on an S600 engine unless you have a POSITIVE diagnosis.

Even MB dealers will "rewire" left and right ignition parts to diagnose. before ordering and changing expensive parts.

learpot

Thanks very much guys. It happens again today. Will take it to shop tomorrow. Will update again. Dan

trustz

Hi, sorry to bring this old one back, but I have a 2005 S600 and I got exactly same problem as yours. Its my second car so I drive only once or twice a week ! Please let me know if you solve the problem or not. thanks

PhazonPhobe

I can't really offer any help, but I have had the same problem on both my old '04 S600 and my current '03 S600.

It seems to happen after I drive it real hard and don't give it a chance to relax before I turn it off. Both of them did it from the time of purchase. I put about 15k miles on each of them.

The problem would always go away after turning the car off and back on. Usually the check engine will stay on until the car is driven 3 times. Knock on wood, hopefully it's not coil packs. =X

trustz

I finally took my s600 to a local Mercedes shop and they said is my left coil pack and they will charge me $1700 for parts and labor and guaranty that's the problem. Since I can get the parts $350 cheaper and $200 cheaper for labor( my friend used to work on MB shop will do it for $100). I just want to make sure its my left coil pack and not something else !

PhazonPhobe

That's exactly what I'm afraid of. And unfortunately, that's not a crazy price. From what I've seen, each of the 2 coil packs run $1300 - $1400 a pop.

If you're slightly mechanically inclined, it shouldn't be too difficult for you to do yourself and save the extra labor cost as well.

tusabes

They are $800 at oreilly with a lifetime warranty

It's the same part mb sells in a different box

PhazonPhobe

This is good to know. I think I can get a discount with my old student ID also.

*knock on wood* Hopefully it won't be for a while though.

trustz

So I went there and found there are two brand of coil pack ,one is made by Import Direct Ignition for $ 820 and the other one is from BWD for $1,236.
So the Import Direct Ignition is the OEM one ? Just want to confirm because I don't want to get some aftermarket one that I will not trust and the difference is only for $200 !!

tusabes

They are all oem just in a different box
As long as it has lifetime warranty you are covered

trustz

For some reason, they are NOT available anymore: confused:

Back to dealer and get 25% discount and free shipping !

kraut56

Before you spend all that money, be aware of the red silicone inserts that go into each of the coil tubes; replacement is mandatoy by MB on coil pack removal/replacement ($ 2.50 each).

I had one that consistently misfired on acceleration cyl # 12 (hardest to get to), the coil had fired straight to the plug side tube and burnt a hole thru the silicone.

Replaced it and never had a misfire again.

Russell Ormerod

First thing I would do is give your car a decent drive. 100km or so and keep the revs up around 3000 rpm. When last did you change the spark plugs? Misfire on a complete bank. I would look at the transformer output. Sometimes I rewire them to see if the fault goes to the other bank. Be careful there is high voltage there. Look at ionic currents between left and right bank to see if the coil pack is failing.

kraut56

agree, see my post # 5 above

trustz

Hi All,

I have a 2005 S600 and experience the same issue with OP, finally I purchase the left coil pack (All the code are for left coil ) from Mercedes ( $1050 shipped) and install it last month. So far no issue or problem on start up anymore !!! Now I am ready for some power upgrade !