OBDll Scan Code P0441on 96 C280 - PeachParts Mercedes-Benz Forum

Martineau Gauda · #1 06-26-2002, 05:51 PM

Just pulled scan code P0441 (Evaporative Emmission Control Incorrect Purge Flow)

It is my understanding that this may be a stuck purge valve.

I need to confirm that the valve is bad. Can I apply 12volts directly to the two terminals of the valve after removing the harness plug and observe if the valve operates.

Is this part available as a generic. I was quoted $138
for the part from dealer.

Thanks

engatwork · #2 06-26-2002, 06:55 PM

Put the +12 v wire to one side and ground the other. If it switches it is ok. If you find it ok then you will need to "rod" out your egr tube from the valve to the intake manifold. It is going to be plugged at the manifold end. Try to run an old speedo cable down through it while turning the cable with a drill motor. It is kinda a pia type of job but is doable by a diyer. I've had to rod mine out a couple times.

Arthur Dalton · #3 06-26-2002, 08:32 PM

The purge valve is energizes by the ECU when the engine is warm. The sig is an oscillating on/off frequency so as not to cause a large vac leak on the engine. By holding the valve in your hand ,you can feel the on/off oscillations.
When you do , pull the vac line of the valve on the outlet side and feel for suction at the valve port.

They have a tendency to stick and sometimes a slight rap gets them going again.
If no beat is felt , use at test lamp at the plug and you should see a clicking on/off lamp.
You may also check for vac. at the intake side of the valve just to verify eng vac to the valve.
I have hads luck with sticky Purge valve operation by squirting WD-40 in the hose between the valve and the charcoal canister and then rehooking up the line to pull the lube into the valve assem.
Also, I have seen purge valves that stick in the open position. This will cause an evasive internal vac leak noticed by rough idle
and other vac leak symptoms. This can be check by unplugging the electric connector and feel for suction at the outlet port. There should be none...

Martineau Gauda · #4 06-26-2002, 08:43 PM

I will check the valve and let you know. Great help from the members of the group. There is a lot of experence and wisdom out there!

Many thanks

euro 287 · #5 06-26-2002, 09:30 PM

Do yourself a favor and remove the tube from the back of the egr valve and disconnect it at the intake , clean the carbon out of it. Clear your code and dont waste any money on a new purge valve. ( incorrect flow) Done this on alot of 104 ,111,120 motors.

engatwork · #6 06-27-2002, 07:04 AM

oops - I had switchover valve in mind

The line from the egr valve to the intake probably just needs rodding out.

Martineau Gauda · #7 06-27-2002, 09:34 AM

Removed valve from car. It was easy to remove. Tested with 12 volts and nothing happened, no clicks. Sprayed "Blaster" into both sides and waited overnight. The valve freed up and I placed some Marvel Mystery Oil into both ports. Waited one hour and reinstalled in car.

It's alive! It's alive! I can feel the valve pulsations of the ECU pulse modulation. The valve is mostly silent but feels like a heart beat when you hold the valve.

This should remedy the EVAP purge flow fault PO441 code.

Hope this lasts. It could be the problem with these valves is a build-up of fuel varnish.

Thanks for all the help

Arthur Dalton · #8 06-27-2002, 10:35 AM

M.G.
That should do it..
I was going to mention a little "Heart Beat" feel to it in my previous post , so glad you mentioned that..
Now that it is free, I would clear the Blaster out with WD for fear of a possible chemical reaction to the valve interior parts....

Arthur Dalton · #9 06-27-2002, 10:39 AM

PS
How about a pic of the Rolls ????
Tnx

Martineau Gauda · #10 06-27-2002, 10:53 AM

Arthur

You are obviously a gentleman of taste and distinction! I will scan and post a picture.

Thanks

dordal · #11 11-20-2002, 01:01 AM

Entering this in the archives for the record:

I had a badly stuck purge valve that I fixed tonight. If spraying WD-40 into the vacuum hose doesn't work, try spraying directly into the valve (both sides) and then turn the valve upside down and let it sit. After a few minutes, turn it back over, shake any extra WD 40 out, and apply about 16V to the terminals repeatedly until it starts clicking. The voltage is a little higher than spec, but it will help force the solenoid to actuate. Repeat if necessary.

To test it when you're done, try to blow through the valve. You shouldn't be able to blow unless you apply current to the terminals, which will open the valve.

unkl300d · #12 03-08-2007, 05:59 PM

For the archives, on another similar thread Gilly described:

""This type of code is usually a sticky purge valve itself. This is located in the left front fenderwell area under the hood, has one wiring connector and 2 purge hoses (rather large hoses, like oversized vacuum hoses) running to it. It also has a symbol on top that says "MOT" and an arrow. You may have noticed this before, it clicks away rather loudly when the engine is warmed up and at op temperature. If you get the engine warmed up and don't notice this valve clicking, then it's probably in need of replacement. Sometimes you can slap this valve a couple times and it will start clicking, another good indication that it's getting lazy and in need of replacement. I've replaced quite a few of them. It's fairly common to have this fail, kind of like the mass air flow sensor, all manufacturers are having problems with this part.Gilly""

OK so, with info from both threads, I ran my 1995 C280 whcih had the same
PO441 check engine light code, up to normal temp and the valve did not feel active.
I removed the valve, easy enough, and sprayed liberal amounts of WD40 into both inlets. Only one side will take up most of the liquid. Turned the valve upside down and let it sit for about 10 min. Then I tested momentarily with a 12 volt source. It did click so I was satisfied that it worked electrically.
Before reinstalling, I sprayed in more wd40 and let it sit upsidedown for some more.
Removed excess and shook it around. Installed it.
The engine was already close to operating temp when I removed the valve. At first I felt nothing overt and was trying to decipher whether the slight illusion of a frequent vibration was the valve or the chassis.
As I was about to measure the harness socket with a test lamp, the valve began to really thump like a "heart beat". It is very palpable, not a sublime sensation.

So, now I have the battery disconnected to reset the CEL light and hope for the best.

At least I know that the valve is easy to remove in the event that I have to relace it later with a new one from FastLane.

Thanks to this forum's members!!