2000 CLK 320 codes for those that love a challenge :)
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2000 CLK 320 Convertible
2000 CLK 320 codes for those that love a challenge :)
Hello all! I'm a long time lurker, first time poster 
I own a 2000 CLK 320 Convertible. The CEL is on (obviously lol). I had it diagnosed earlier today at a shop, so here goes:
P0400: EGR Valve CURRENT AND STORED
P0300-067: Misfiring NOT DEFINED
P0302-072: Misfiring of Cylinder 2 NOT DEFINED
P0305-073: Misfiring of Cylinder 5 NOT DEFINED
P0300-080: Misfiring Damages TWC STORED
P0302-085: Misfiring of Cylinder 2 Damages TWC STORED
P0305-086: Misfiring of Cylinder 5 Damages TWC STORED
P0303-083: Misfiring of Cylinder 3 Damages TWC STORED
P0306-084: Misfiring of Cylinder 6 Damages TWC STORED
3 days ago my mechanic cleared the codes because it was rough idling, running really hard like it had no gas, and the CEL flashed. Prior to this I also had codes for the Fuel trim for bank 1 and 2, not sure which sensors, and I can't remember the code number, sorry.
I ordered a new EGR Valve, I was thinking about getting new O2 sensors, I'm just not sure which ones or if it will even help. I also considered the MAF, but I decided to clean it before replacing it.
I also just replaced the ignition key, not sure if that matters......Plus I'm almost 2 k over Service B.
Now that I've aired all my dirty laundry, I'm begging for help.
PLEASE.
And no, I didn't do most of the damage, the CEL was on when I bought it.
I own a 2000 CLK 320 Convertible. The CEL is on (obviously lol). I had it diagnosed earlier today at a shop, so here goes:P0400: EGR Valve CURRENT AND STORED
P0300-067: Misfiring NOT DEFINED
P0302-072: Misfiring of Cylinder 2 NOT DEFINED
P0305-073: Misfiring of Cylinder 5 NOT DEFINED
P0300-080: Misfiring Damages TWC STORED
P0302-085: Misfiring of Cylinder 2 Damages TWC STORED
P0305-086: Misfiring of Cylinder 5 Damages TWC STORED
P0303-083: Misfiring of Cylinder 3 Damages TWC STORED
P0306-084: Misfiring of Cylinder 6 Damages TWC STORED
3 days ago my mechanic cleared the codes because it was rough idling, running really hard like it had no gas, and the CEL flashed. Prior to this I also had codes for the Fuel trim for bank 1 and 2, not sure which sensors, and I can't remember the code number, sorry.
I ordered a new EGR Valve, I was thinking about getting new O2 sensors, I'm just not sure which ones or if it will even help. I also considered the MAF, but I decided to clean it before replacing it.
I also just replaced the ignition key, not sure if that matters......Plus I'm almost 2 k over Service B.
Now that I've aired all my dirty laundry, I'm begging for help.
PLEASE. And no, I didn't do most of the damage, the CEL was on when I bought it.
MBWorld Fanatic!
Joined: Apr 2005
Posts: 3,784
Likes: 84
From: SCV SoCal
2002 CLK430
The original equipment O2 sensors are due and they can make the engine idle poorly. I also recommend replacing the MAF. It's a simple task and a real Bosch unit is inexpensive. There is a DIY with photos on my website.
MBWorld Fanatic!
Joined: Dec 2011
Posts: 1,273
Likes: 129
From: Orlando, FL
2015 GL550 4matic
Get an OBD2 reader and map the O2 sensor data. This can be achieved with a bluetooth OBD2 for less than $10 on Amazon, and the free Torque app on your phone. Set up graphs for each O2 sensor so you can watch them simultaneously. Once the car is properly warm, hold it at about 2000 rpm. The forward sensors should show an up-down oscillating graph, the rear sensors should show a relatively flat line. If you get weird graphs, then you have either a bad sensor, or a bad cat. If the graphs look normal, then I would not bother replacing the sensors.
Probably the EGR is all gummed up, and what got past there has fouled up your intake manifold.
Other standard maintenance would include check/replace the most likely cracked vent hoses on top of the engine, as well as vacuum tubes coming off the intake manifold; replace plugs and wires if condition/age is questionable; possibly replace the MAF, but I don't know if these symptoms sound like others who have MAF issues, and I think it would normally give you a different code for MAF.
Probably the EGR is all gummed up, and what got past there has fouled up your intake manifold.
Other standard maintenance would include check/replace the most likely cracked vent hoses on top of the engine, as well as vacuum tubes coming off the intake manifold; replace plugs and wires if condition/age is questionable; possibly replace the MAF, but I don't know if these symptoms sound like others who have MAF issues, and I think it would normally give you a different code for MAF.
