Check Engine Light/P0411 Code also Engine is IDLE'ING ROUGH

[jay_jay_n]

Hi guys.. well i just barely picked up my DAD's 95 c280 and its been good the first week and noticed the check engine light came on. I rented a OBD II Scanner and read the codes -

PO411 comes up as "Secondary Air Injection Improper Flow Detected

i haven't found any information on this issue and wondering if u guys have any idea how to fix this?

Also just recently a week after this code the car is now idleing around 500-600 and is very rough seems like it wants to die or something on stop and go traffic.. it isn't as bad when its in Park.. but its still noticiable.. From what i have read it Possibly could be the MAF sensor but i'm unsure how to tell if it is the problem since the code for it hasn't come up and since a common symptom for the sensor failing is jerkyness on shifting and the shifts so far has been smooth.

another issue that maybe u guys can help also is that my gas gauge doesn't want to come up sometimes the light for low gas still comes on when it is low.. also the speedometer doesn't work unless i hit the gauge cluster.. i'm starting to assume its the guage cluster.. but i'm unsure if this is a common problem with other 202's.

Thanks you guys and my 202 has just above 100,000 :)

[Proven Guilty]

air mass meter

[jay_jay_n]

any way of testing it to kno if it is or not working? i read up about testing the voltages but i don't really want to open up the rubber cover of the sensors connector so i can test voltages... unless theres another way?

[htfan1]

I had the exact same "PO411" error on my 95 C220.

It ended up being a bad vacuum line. Once I replaced it a reset the CEL, it's been fine.

[xvvvz]

>>i read up about testing the voltages but i don't really want to open up the rubber cover of the sensors connector so i can test voltages<<

Do you have reference for how to do this testing? Please post if you do.

Thanks,
Doug

[jay_jay_n]

Originally posted by jay_jay_n
any way of testing it to kno if it is or not working? i read up about testing the voltages but i don't really want to open up the rubber cover of the sensors connector so i can test voltages... unless theres another way?

ohh really any chance kno which one or how did figure it out? i have a mighty vac and don't kno if i can test the vacuume lines like i would a honda..




Originally posted by xvvvz
>>i read up about testing the voltages but i don't really want to open up the rubber cover of the sensors connector so i can test voltages<<

Do you have reference for how to do this testing? Please post if you do.

Thanks,
Doug

sure man i got the info from benzworld here is what it said.

http://www.benzworld.org/forums/w202-c-class/1215613-mass-air-flow-sensor-what.html

"I thought I would drop by and give you a DIY test for
that component.

Just the blah,blahs as follows;
One wire supplies power,a second for the ground and
a third for the signal.The other two are for the burn
off cycle when you shut your engine down(power and ground).

Test; function;
Start the engine and let it idle.The signal wire will
have a voltage between 0.25 and 4.75 volts.At idle the voltage should be low and as you increase the rpm's,the voltage increases.If this does not occur,
check for 12 volts between the sensor and ground.If cool do a resistance test and the readings should not be above 1000 ohms and if any higher replace.

Hope this little test saves you some money in the future[8D]Take it easy!Bye"


i guess it is a possibility that the vacuume line would be effecting my idle.. but i thought vacuume lines would make my idle be irratic not drop it..

[jnenad16]

secondary air injection is your air pump. improper flow would most likely refer to a broken/leaking hose between the pump and the EGR valve or a clogged line between the EGR valve and the intake manifold/throttle body.

nenad

[xvvvz]

Thanks for the link, Jay. Ha, ha, I obviously had read the later parts of that thread but missed the part you referenced or didn't read back far enough.

I am a bit of an of a electro idiot so I am not knowledgeable enough to know which of the wires is which (I would guess the brown would be the ground) therefore I fear I would probably end up toasting something expensive ;)

Doug

[Sulaco]

On the instrument cluster:

Common problem. Those little black needles that the gauge'ss orange-hands rest upon get sticky over time. There's a part number floating around here somewhere for little covers to slip over those to fix the problem.

Personally, I removed my steering wheel, pulled the instrument cluster, disassembled it, and cleaned the needles with cotton and alcohol. Worked for about 6 months :(

Now I need to clean them all over again.

[black96benz]

Yeah I had that same code on my 96 c220. Secondary air injection is the air pump. The power cable to mine burned and became loose. Just had to clean the connector and crimp it back on to the air pump. NO problems since and its been 20,000 miles.

[jay_jay_n]

Originally posted by Sulaco
On the instrument cluster:

Common problem. Those little black needles that the gauge'ss orange-hands rest upon get sticky over time. There's a part number floating around here somewhere for little covers to slip over those to fix the problem.

Personally, I removed my steering wheel, pulled the instrument cluster, disassembled it, and cleaned the needles with cotton and alcohol. Worked for about 6 months :(

Now I need to clean them all over again.

thank you for that.. i'm glad its a easy fix :)



Originally posted by black96benz
Yeah I had that same code on my 96 c220. Secondary air injection is the air pump. The power cable to mine burned and became loose. Just had to clean the connector and crimp it back on to the air pump. NO problems since and its been 20,000 miles.

thx do u have a pic of where the air pump is? also would this cause my rough idle and slow response? or is it something else like the MAF?

[black96benz]

No pic, but it is on the passenger side on the front corner of the engine toward the radiator. It has a power cable and and 3 inch hose on it. Its black and little smaller than an alternator. Hopefully its not bad because its an 800 dollar item from the stealership around 500 online.