lacelane

Got about 255k miles on it now. Still looks sweet. But now it's throwing all kinds of engine codes. P1071 at first, then after clearing codes, after say, the second time I start the car, and drive a few feet. Rough idle. It's like the car wants to jump when i'm at a stop. Multiple misfires. You guys think if I get the WIS computer software and hook up the obd2, I can find out what the problem is? I'm thinking that it's running too lean? Here are the fault codes:

Car Scanner ELM OBD2
DTC report
Selected brand: Mercedes-Benz
VIN: WDBRF40XXXXXXXXXXX

============1==============
P201C
Raw code: 201C
ECU: 01
Status: Test has not been completed, Validated and stored in non volatile memory
OBDII: Intake manifold air control actuator, bank 2 - supply voltage low
============2==============
P201B
Raw code: 201B
ECU: 01
Status: Validated and stored in non volatile memory, Validated fault has been present during this drive cycle
OBDII: Intake manifold air control actuator, bank 1 - supply voltage low
============3==============
P2029
Raw code: 2029
ECU: 01
Status: Test is inhibited by other DTC, Validated and stored in non volatile memory, Validated fault present at time of request, Validated fault has been present during this drive cycle
OBDII: Auxiliary heater (fuel fired) - system disabled
============4==============
P0302
Raw code: 0302
ECU: 01
Status: Pending
OBDII: Cylinder 2 - misfire detected
============5==============
P0304
Raw code: 0304
ECU: 01
Status: Pending
OBDII: Cylinder 4 - misfire detected
============6==============
P0303
Raw code: 0303
ECU: 01
Status: Pending
OBDII: Cylinder 3 - misfire detected
============7==============
P0300
Raw code: 0300
ECU: 01
Status: Pending
OBDII: Random/multiple cylinder(s) - misfire detected
============8==============
P0171
Raw code: 0171
ECU: 01
Status: Pending
OBDII: System too lean, bank 1
============9==============
P0304
Raw code: 0304
ECU: 01
Status: Confirmed
OBDII: Cylinder 4 - misfire detected
============10==============
P0303
Raw code: 0303
ECU: 01
Status: Confirmed
OBDII: Cylinder 3 - misfire detected
============11==============
P0300
Raw code: 0300
ECU: 01
Status: Confirmed
OBDII: Random/multiple cylinder(s) - misfire detected
============12==============
P0171
Raw code: 0171
ECU: 01
Status: Confirmed
OBDII: System too lean, bank 1

lacelane

I'd also like to mention that the mpg is absolutely horrible. I'm getting about 14.7 to 16 mpg on the streets, if I'm lucky I can get 21 mpg on the freeway.

5by5

I got the P0171 and misfire codes on my daughter’s 2003 c230. She was out of state at the time and the local mechanic replaced plugs and MAF. Didn’t fix it.

Turned out to be oil contamination in the engine wiring harness from leaks at the cam magnets. Replaced magnets, installed harness pigtails and degreased the wiring harness the best I could. It will still throw an occasional code but runs good.

I’d make sure you have the pigtails on the harness and that the connectors aren’t oil soaked. If they are soaked, you can get all sorts of spurious codes.

slammer111

There was a recall for this. Talk to the dealer and bring your VIN. If all the codes suddenly appeared overnight then this is the most likely cause.

With that mileage you also might want to replace all the spark plugs and ignition coils if you haven't done so. The service life for the coils is 160k but didn't actually die on me until 200k or so. Spark plugs still looked good when I changed them out at 180k so I'll probably run my current set longer.

5by5

My understanding is that MB-USA terminated the service bulletin. At least, that’s what they told me last year.

Too bad, if it were still in effect, they’d likely had to replace the harness, magnets, and possibly the ECU and O2 sensors. They quoted about $5k...

slammer111

The only thing that really has to be replaced per se is the leaking cam sensors and the addition of the pigtails. The oil can be soaked out of the harness. Bit of a pita but it's doable.

lacelane

Thanks y'all. I'm gonna check my spark plugs first, just bought the spark plug tool head and check the ignition coils. It's got 255k miles on it, so I guess it's overdue. I saw a whole bunch of car videos and the symptoms similar to spark plug problems. As for the recall, The car has gone through all the services. Tubes has been all replaced when it was recalled. We will see on the spark plugs.

lacelane

Would any of you be kind of enough to post a picture on what a pigtail looks like? Can it be seen without removing all kinds of heavy stuff? Thanks.

slammer111

Some photos can be found here. They can be seen simply by popping the hood. Leaking cam sensors pigtails

jggarcia.vc

Not sure if you've installed the pigtails but on the forum I was given this part # 271-150-02-56-05-MBZ yet when I went back and looked at your post the part # was 271-150-27-33-64-MBZ they look like the same harness in the images not sure what the difference maybe?