W220 S500 Misfires on 5-8 cylinders.
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S500 w220
W220 S500 Misfires on 5-8 cylinders.
When I am driving the car normal it runs fine. Just as soon as I kick the transmission down the check engine light flashes and it starts missing. It will continue missing until I restart the car. Then it all returns to normal.
I took it to a local indy shop. They said that my driver side cats were bad. Here is where I have a problem. The car runs fine until I give it the gas. Then it will reset as soon as it starts back up. The codes it is throwing are misfires on 5-8 cylinders. I am thinking that it may be something electronic like a MAF or pedal sensor.
Thank you for the time to share your experience with me.
I took it to a local indy shop. They said that my driver side cats were bad. Here is where I have a problem. The car runs fine until I give it the gas. Then it will reset as soon as it starts back up. The codes it is throwing are misfires on 5-8 cylinders. I am thinking that it may be something electronic like a MAF or pedal sensor.
Thank you for the time to share your experience with me.
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From: North Carolina
2003 S500 - Toyota Corolla (in the rain)
BY the way, what year is your car and how many miles?
Cylinders 5-8 are on the driver's side and cylinders 1-4 are on the passenger side. The firing order is 1-5-4-2-6-3-7-8.
Lots of possibilities but since it is isolated to one side I tend to agree with the Indy although we both could be wrong.
An inexpensive thing to do is take the MAF out and clean it. Use the CRC MAF Cleaner. Don't try using anything like a brake cleaner. The CRC stuff is less than $10 for a can of spray.
Cylinders 5-8 are on the driver's side and cylinders 1-4 are on the passenger side. The firing order is 1-5-4-2-6-3-7-8.
Lots of possibilities but since it is isolated to one side I tend to agree with the Indy although we both could be wrong.
An inexpensive thing to do is take the MAF out and clean it. Use the CRC MAF Cleaner. Don't try using anything like a brake cleaner. The CRC stuff is less than $10 for a can of spray.
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S500 w220
It is a 2004. I have 160K on it now.
I did clean the MAF and it seemed to help a bit. When you push the gas pedal down enough to drop it down it into passing it starts missing still (and throws a the codes).
Is there anything else that could be messing up with just one side?
I did clean the MAF and it seemed to help a bit. When you push the gas pedal down enough to drop it down it into passing it starts missing still (and throws a the codes).
Is there anything else that could be messing up with just one side?
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From: North Carolina
2003 S500 - Toyota Corolla (in the rain)
Awful strange that the problem only occurs on the one side. Rather than throwing a lot of money on parts that you might not need it might make sense to have someone hook it up to a MB STAR diagnostic system. If you don't have an INDY in your area with the system your local MB dealer will do it but will charge probably around $150. Where are you located, several members on here have the diagnostic system.
You should probably update your USER CP and include the year of your car and location just for future reference.
You should probably update your USER CP and include the year of your car and location just for future reference.
MBWorld Fanatic!
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Posts: 1,284
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From: North Carolina
2003 S500 - Toyota Corolla (in the rain)
Tusabes the V8 has 8 ignition coils, 4 on each side. Each cylinder has it's own ignition coil. It seems extremely unlikely that all four on one side would fail although it's not impossible.
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S500 w220
Not a lot of faith in these independent shops.
I read that I could take the O2 sensor out and if it was the cats it would run fine.
Anybody in the Cincinnati OH area with a STAR reader?
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S500 w220
So here is the end result. I put the car on jack stands and took a rubber mallet and first pecked on the front cats. No sound at all. Went to the back cats pecked on them. Sounded like there was a bag of marbles in them.
After a trip to the hardware store (I had to buy a carbide saws all blade as the exhaust is stainless), I cut the back cats out. The insides of the front cats were sitting in the rear ones and down most of the pipes.
The back cats were toast so I beat them out. I'll replace them later in the winter. The car is running great now. No CEL.
After a trip to the hardware store (I had to buy a carbide saws all blade as the exhaust is stainless), I cut the back cats out. The insides of the front cats were sitting in the rear ones and down most of the pipes.
The back cats were toast so I beat them out. I'll replace them later in the winter. The car is running great now. No CEL.
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From: Tampa, FL
2000 S500
Bill,
Thanks for posting. I'm having the exact same problem. When you cut out the rear cat did you just cut out the drivers side? Did you weld it back in or put in a straight piece of pipe in its place? Also did you disconnect the O2 sensor(s), if so which one(s).
Thanks
Thanks for posting. I'm having the exact same problem. When you cut out the rear cat did you just cut out the drivers side? Did you weld it back in or put in a straight piece of pipe in its place? Also did you disconnect the O2 sensor(s), if so which one(s).
Thanks
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From: Just north of Detroit,Michigan
2012 E350 4Matic P2
I had a similar problem but my left rear Cat was rattling at idle. Very annoying to say the least. I chose to gut my Cats instead of cutting them out and replace with straight pipes. Anyway, my story here.
As to the CEL, I never had a performance issue just the rattling. Since the O2 sensors are up stream of the rear Cats, ECM sees no change.
Good Luck,
Bob
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S500 w220
Bill,
Thanks for posting. I'm having the exact same problem. When you cut out the rear cat did you just cut out the drivers side? Did you weld it back in or put in a straight piece of pipe in its place? Also did you disconnect the O2 sensor(s), if so which one(s).
Thanks
Thanks for posting. I'm having the exact same problem. When you cut out the rear cat did you just cut out the drivers side? Did you weld it back in or put in a straight piece of pipe in its place? Also did you disconnect the O2 sensor(s), if so which one(s).
Thanks
A couple things.
One....not sure what the pipes are made out of, but I am pretty sure there is unicorn tears and diamonds in it. Regular sawsall blades did nothing. I mean they just scratched the surface before the teeth were gone. I went to Home Depot and got a stainless blade and I got got two cuts out of the blade. I might be able to get 2 more before it is toast. Those pipes are super hard!
Two. I just hollowed out the Cat and put it back in. I used some adapters to get it back together. I would recommend getting the mandrel that stretches the diameter of the pipes for a better fit from Harbor Freight. Mine did not seal real good and I am going to have to go back and fix it. With the hollow cat it is much louder than what it was before. I would say with a strait pipe you would not get that growl. I hollowed mine out because I wanted to use the super hard material that is really corrosion resistant.
I have not had one issue with the O2 sensors at all.
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s class w220 s320 1999
hi i have a UK spec W220 3200cc and have had the same problem with a misfire under hard acceleration which fixes itself when i switch of the engine. It has taken me a while after many fault code reading with various bits of equipment suggesting MAF , Coil Pack , Lambda sensor etc. I can confirm my fault was low transmission oil level! I was about to spend a fortune on a maf sensor and coil packs when i realised i had a minor transmission leak so topped up the level by guessing as there is NO dipstick just in case and the car drives like a new one and will rev to its normal limit. NO misfire or engine management lights and smooth on both upshift and downshift, Happy days. Just for the record Transmission including Torque converter holds 8.5 Litres of fluid. Mercedes suggest fully synthetic although Dexron 2 will be fine. Happy Motor Mechanic Again !
