Random CEL help!!! E55 Guys LOOK INSIDE
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Random CEL help!!! E55 Guys LOOK INSIDE
PLEASE HELP FELLOW MEMBERS
Ok so a total of about 3 times over the course of a year my cars check engine light has come on.misfire..... 1st senario the first time It happeded was around last November when I got it. I took it to Advanced auto pulled the codes and it was multiple cylinder misfire. Cleared the code fired it up problem solved. I decided to replace all the Plugs with one step colder NGKs.
2nd Senario same thing cleared the code came on about 2 months after I replaced the plugs, Restarted issue gone.
3rd Senario Tonight Cel came on the way home from work, Started to run rough, CEL flashed for a few times then went solid. Pulled over and scanned codes p3005 p3006 p3007 p3008..... Cleared Fired up and came right back on. Cleared again and ran for a minuite and came back on.
Whats going on here guys?...........
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From: Mississippi
2004 SL55
PLEASE HELP FELLOW MEMBERS
Ok so a total of about 3 times over the course of a year my cars check engine light has come on.misfire..... 1st senario the first time It happeded was around last November when I got it. I took it to Advanced auto pulled the codes and it was multiple cylinder misfire. Cleared the code fired it up problem solved. I decided to replace all the Plugs with one step colder NGKs.
2nd Senario same thing cleared the code came on about 2 months after I replaced the plugs, Restarted issue gone.
3rd Senario Tonight Cel came on the way home from work, Started to run rough, CEL flashed for a few times then went solid. Pulled over and scanned codes p3005 p3006 p3007 p3008..... Cleared Fired up and came right back on. Cleared again and ran for a minuite and came back on.
Whats going on here guys?...........
Do you have access to a STAR system? That can probably diagnose the issue...I just hate paying for it every time I need something diagnosed.
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
I think I kinda defer to RLH above on this one. When I had something as simple as 2 wires crossed on one O2 sensor, the friggin car was going haywire with misfire CELs.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
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From: Mississippi
2004 SL55
I think I kinda defer to RLH above on this one. When I had something as simple as 2 wires crossed on one O2 sensor, the friggin car was going haywire with misfire CELs.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
Like I said, it would probably save you a lot of time and frustration to bite the bullet and let someone w/ STAR look at it.
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
Snagged this from a 65 forum post
Worth double checking your gapping on the cyls in question throwing CELs. Not sure what the gapping is for the 55s....just thought that might be a angle.
Did they gap your spark plugs? There is an MB bulletin that states that the spark plugs must be gapped to .27cm if i recall correctly the ones at the dealer come with a .70cm gap. It will cause the car to misfire. Give it a shot.
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
last one of the night and THIS is one I would really put some thought into. Clogged cat. Heard of this more than once.
This poor guy spent 4500$ to figure out it was clogged cat causing misfires. Least the cat was covered under warranty.
I forgot though. I have floored fab heads like you BUT 100 cel race cats. Aren't you cat-less?
If so DAYUM! I would have thought we might be onto something.
Here's the post from the other guy
This poor guy spent 4500$ to figure out it was clogged cat causing misfires. Least the cat was covered under warranty.
I forgot though. I have floored fab heads like you BUT 100 cel race cats. Aren't you cat-less?
If so DAYUM! I would have thought we might be onto something.
Here's the post from the other guy
and the answer was a clogged cat converter, lucky i was under the federal 8year 80k miles warrentee so i got it replace for free at the dealer...
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05 E55 AMG, E320 CDI, Turbo E46 M3,IS300 2JZGTE,VQ35 Turbo Maxima, Mercedes 300D
Did you pull any of the plugs to see what the plugs look like? Were they fouled or anything? The plug can tell you a lot, a CEL code .. not a huge amount. could be fueling or fuel trim issue especially with headers and messing with O2s. Gap size may be a factor also. I tend to set mine a little smaller under increased boost. Some people say colder weather has an effect though I personally have not experienced this. Also talk to whoever tuned your car if they have any thoughts on the subject.
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I assume you meant the code was P0300, P0305-P0308? The same thing happened to me after I had my FF LT's installed. Originally I extended the sensors and couldnt get misfire CELs to stop. I then bought all new sensors and extended from the harness. Since then, the misfire codes have stopped, but I have a CEL for O2 heaters that stays on permanently. However, the car runs fine (knock on wood!!). I even got my car tuned w/ the CEL on and it still runs fine. I know this didn't answer your question, but I was very frustrated with those misfire CEL's; almost to the point of going back to my stock setup.
Do you have access to a STAR system? That can probably diagnose the issue...I just hate paying for it every time I need something diagnosed.
Do you have access to a STAR system? That can probably diagnose the issue...I just hate paying for it every time I need something diagnosed.
I think I kinda defer to RLH above on this one. When I had something as simple as 2 wires crossed on one O2 sensor, the friggin car was going haywire with misfire CELs.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
Just don't get why it's not constant?????
You driving in rain or wash her today? Just curious. Mine freaks and throws misfires then too.
last one of the night and THIS is one I would really put some thought into. Clogged cat. Heard of this more than once.
This poor guy spent 4500$ to figure out it was clogged cat causing misfires. Least the cat was covered under warranty.
I forgot though. I have floored fab heads like you BUT 100 cel race cats. Aren't you cat-less?
If so DAYUM! I would have thought we might be onto something.
Here's the post from the other guy
This poor guy spent 4500$ to figure out it was clogged cat causing misfires. Least the cat was covered under warranty.
I forgot though. I have floored fab heads like you BUT 100 cel race cats. Aren't you cat-less?
If so DAYUM! I would have thought we might be onto something.
Here's the post from the other guy
Did you pull any of the plugs to see what the plugs look like? Were they fouled or anything? The plug can tell you a lot, a CEL code .. not a huge amount. could be fueling or fuel trim issue especially with headers and messing with O2s. Gap size may be a factor also. I tend to set mine a little smaller under increased boost. Some people say colder weather has an effect though I personally have not experienced this. Also talk to whoever tuned your car if they have any thoughts on the subject.
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From: Bloomingdale,IL
2004 W211 E55K, GL550
In order check wires they maybe arching u can maybe check them by spraying them with a bottle of water and see if there is a spark outside of the wire, 2 it maybe a possable coil problem, and 3 which i hope it is not it could be maybe a bad cylinder i had a misfire issue with my car and it ended up being a faulty cylinder which required a engine overhall. I would check compression & pull your plug to see if there is any oil or any damage to the plug. Hope that helps and good luck.
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From: Northern VA
W211
sorry to hear this problem my friend had misfire codes left/right and in the end, it was bad gas that he got. He changed plugs, wires, coilpacks, CPS, and the mb mechanic he used put in some BG44k on empty tank and ran it for 20mins hard. Afterwards, no more CEL codes.
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2006 E55 AMG
Here you go:
http://www.obd-codes.com/p0300
http://www.obd-codes.com/p0305
http://www.obd-codes.com/p0308
I know that Pullejo had some CEL issues after he installed the Floored Fab Longtubes, send him a pm as he got it sorted out. He also has a Eurocharged tune so maybe Jerry adjusted the some mapping.
http://www.obd-codes.com/p0300
http://www.obd-codes.com/p0305
http://www.obd-codes.com/p0308
I know that Pullejo had some CEL issues after he installed the Floored Fab Longtubes, send him a pm as he got it sorted out. He also has a Eurocharged tune so maybe Jerry adjusted the some mapping.
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From: Northern VA
W211
P0305 Cylinder 5 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0308 Cylinder 8 Misfire Detected
A code P0305 may mean that one or more of the following has happened:
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
P0306 Cylinder 6 Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0308 Cylinder 8 Misfire Detected
A code P0305 may mean that one or more of the following has happened:
- Faulty spark plug or wire
- Faulty coil (pack)
- Faulty oxygen sensor(s)
- Faulty fuel injector
- Burned exhaust valve
- Faulty catalytic converter(s)
- Running out of fuel
- Poor compression
- Defective computer
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
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From: Mississippi
2004 SL55
Here you go:
http://www.obd-codes.com/p0300
http://www.obd-codes.com/p0305
http://www.obd-codes.com/p0308
I know that Pullejo had some CEL issues after he installed the Floored Fab Longtubes, send him a pm as he got it sorted out. He also has a Eurocharged tune so maybe Jerry adjusted the some mapping.
http://www.obd-codes.com/p0300
http://www.obd-codes.com/p0305
http://www.obd-codes.com/p0308
I know that Pullejo had some CEL issues after he installed the Floored Fab Longtubes, send him a pm as he got it sorted out. He also has a Eurocharged tune so maybe Jerry adjusted the some mapping.
Seems like several people that installed FF LT's have had misfire CELs. I changed my plugs as well and that didn't fix it. I've spent ~$1000 diagnosing the problem, changing the plugs, labor, etc. and I still have the heater CEL on. I constatnly look at the solid CEL and wait for it to start blinking again.
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Seems like several people that installed FF LT's have had misfire CELs. I changed my plugs as well and that didn't fix it. I've spent ~$1000 diagnosing the problem, changing the plugs, labor, etc. and I still have the heater CEL on. I constatnly look at the solid CEL and wait for it to start blinking again.
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From: Salt Lake City (but not Morm)
2003 E55 & 2014 GL550
Seems like several people that installed FF LT's have had misfire CELs.
How strange.
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Gents car is in service. My only complaint I have with the FF LT headers is the fact that they hit somewhere on the body under heavy exceleration and make a small rattle. Other than that I have No CEL's for Heater, 02s etc. Now we will see what happens when I get the report back soon from service on whats going on, But I soubt its the headers causing the isssue
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