Mercedes-Benz Forum banner

141 - 160 of 169 Posts

·
Registered
98 ML320
Joined
·
97 Posts
89 is obviously ahead of me here, but confirms what I am saying: The air pump on the V6 is right up on top in front of the intake manifold. It is quite easy to remove and all steps seem to be obvious. it doesn't hurt to take a "before" picture.

I removed mine just for easier access to the small vacuum hose which attatches to the BOTTOM of the intake manifold. This hose provides vacuum for the intake manifold plenum sizing valve I DEFINITELY recommend you replace the OTHER two small hoses (in a common sleeve) as they are very likely old and crumbly, as this vacuum source is what opens the two valves on the discharge of the air pump--might fix your problem! .
 

·
Registered
Joined
·
2 Posts
Westsandiego, I am following your lead on this. I have removed the drivers side exhaust manifold and I'm in the process of unblocking the ports. Sounds as though your blockage was right at the port opening. Do you recall how far your pick would go in once the blockage was clear? I can access each port but my pick will only go in about 1/4" at most before it stops. After digging around, I have yet to see any bits of carbon falling out either. Did you observe any while removing your blockages?
 

·
Registered
2001 ML320
Joined
·
21 Posts
The homemade picks I used have a 3/4", 1", and 1-1/8" long tip. It started out similar to your situation where it would not go in all the way. Had to start with shortest tip then work my way up to the longest, as there is not much room to push the tip up from below. After fully dislodging the blockage, the 1-1/8" tip goes all the way in. I did also dip the tip in injector cleaner while picking at the blockage. Once the blockage was opened, I poured 10-15 mL of injector cleaner down the air injection valve, then blew it out each manifold port with compressed air (by blocking 2 of the 3 ports with a towel in order to blow out the 3rd). I did not see any bits fall out but that may be because I was using injector cleaner and it just "dissolved" the carbon plug a little bit at a time. I did hear a "pop" with blowing out one of the ports, indicating a plug flew out. Hope this helps.
 

·
Registered
2000 ML320
Joined
·
28 Posts
I don't post much but after going the route of replacing two secondary air pumps (thinking both were defective), replacing relays, air hoses, check valves, ect.. I decided to open up the secondary air pump "reed" valves to see if any issue lied there.

First, the tool I used on my 265k mile screws that hold the valve on. A regular screw driver proved ineffective, you tap this tool with a small dead blow hammer and it turns the screw in 20° increments:



Took the top halves off before removing the entire assembly from the intake manifold:



The drivers side valve wasn't too bad, it did have about a teaspoon worth of build up, I cleaned it out with carb/choke cleaner.

However, the passenger side valve was almost completely clogged, filled with loose debris, also completely clogged all the way down into the intake manifold. I also was liberal with some carb/choke cleaner in this area. I used a small flat head screwdriver to remove the caked on material.




NOTE: Be careful removing the valve from the intake manifold, they will likely be stuck pretty good. I moved them side to side with soft strikes from a rubber mallet but you can very easily break the press fitting off the bottom of them that goes into the head. Try to spin it rotationally while lifting up versus wiggling front to back side to side, certainly a quick way to break them.

I reset the ecu and I will report back to see if this once and for all got rid of this blasted p0140 so i can pass emissions here in CT!!


Thanks,


Matt
 

·
Registered
1999 ML320
Joined
·
908 Posts
I removed mine just for easier access to the small vacuum hose which attatches to the BOTTOM of the intake manifold. This hose provides vacuum for the intake manifold plenum sizing valve I DEFINITELY recommend you replace the OTHER two small hoses (in a common sleeve) as they are very likely old and crumbly, as this vacuum source is what opens the two valves on the discharge of the air pump--might fix your problem!
I sincerely hope you know what you're getting into. THAT small vacuum hose which attaches to the bottom of the intake manifold SHOULD NOT BE TOUCHED AT ALL!

Without very careful squeeze, the THAT vacuum hose in your 17 years old ML320 will likely crumple into pieces, you'll want to kill yourself. Take time and read this thread; http://www.benzworld.org/forums/w163-m-class/1720750-intake-manifold-vaccum-varible-induction.html

Here's how the hose is connected to the intake manifold. Someone took the time and sliced the port to show us this. Good luck.
 

Attachments

·
Registered
1999 ML320
Joined
·
12 Posts
Revival of thread sorry

So I got the dreaded p0410 code
Pump vacuum and one way valves work
Passenger side exhaust comes out of port the drivers side is completely blocked
Bought BG 211, passenger side 50 cc went right through
Drivers side not draining at all 100 cc in funnel I have removed the liguid and used coat hunger goes in 3 inches put funnel back on 100 cc left over night did not drain at all. Today I removed the liguid and but 100 cc of fresh big 211 not draining at all. Turned the engine manually twice.
Questions :
1) do I put everything back together and start engine ?
2) do I put everything back together change the oil then start the engine?
3) do I just remove the exhaust manifold and try to clean out the ports?
4) can I put seafoam in the oil and intake run the car then change oil ?
I'm trying to pass emissions. It's an ml 320 1999 with 190000 miles on it !!!
Thanks for your help !!!!
 

·
Premium Member
02 ML320 06 ML500
Joined
·
16,982 Posts
The deed has been done, but you should have never poured B211 into the passenger side which was no clogged.

Be it as it may, the instructions call for the manual turning of the eng. at the crankshaft bolt.

If you do not have the proper socket, you should at least change the oil first before starting the eng.
 

·
Registered
1999 ML320
Joined
·
12 Posts
Thank you 43 sqd I did turn with a 17 mm hex manually two times used chalk on the top of the crank shaft pulley turned that two revolutions stopped where my marks lined up. So I llchange the engine oil and try to see ? The passenger side looked gummed up that's why I put 50 cc idk I just hope this helps !!!
 

·
Registered
2004 ML 500
Joined
·
6 Posts
Apologies for the necro-bump. I let the dealer fix the P0410 code 2-3 years ago to the tune of about $1300. Now it's back. Unfortunately I can't find the work order to see exactly what was replaced.

2004 ML500, 124k miles.

1) Air pump spins when 12V is applied to red/white wire.
2) 40 amp fuse is good
3) Relay assumed good - haven't tried swapping
4) Air pump seems to run when engine is started. Might be running again in certain conditions when driving, but I've become so sensitive to engine noises I can't be certain.
5) I have *not* been able to try the "diverter valves open, check for vacuum up top and exhaust gas below" test.
6) Truck has been sitting for several weeks due to other life issues. The last time I started it, I got misfire codes on cylinders 8, 4 and 2 at fast idle, with a hard shudder. Shudder went away when I shifted into drive (moving from driveway to garage).
7) I have not started it since (almost two weeks now)

I took apart the diverter valves tonight - first pic is comparison between passenger side (left) and driver side (right)



Based on the earlier photo of a brand-new reed valve - should they be visibly closed "at rest?"

Driver side valve. Not as bad as some of the photos in this thread. But enough build up to throw a code?



Fault info from my Autel. Does this support an issue with the diverter valves?



And finally, questions about this screen:



The top value is for the status of the secondary air pump. Values for first and last are OFF. As stated earlier, it runs when 12V is applied to the red/white wire. Audibly, it *seems* to be running when I start the truck, but I haven't verified by hand. Maybe relay?

The fuel tank cap status shows up under the misfire code as well. I haven't let the truck sit this long before - not sure if that's a misdirection or not. What should that status be for a properly-working vehicle?

Thanks in advance - hoping to get it back on the road for our beach trip in a couple of weeks. Need the space for gear and low-range for the sand.
 

·
Premium Member
02 ML320 06 ML500
Joined
·
16,982 Posts
The condition (open or closed) of the reed valve has nothing to do with the problem at hand. The problem is one or both of the exhaust ports in the head is blocked with carbon.

Remove the single bolt holding each Shut-off Valve, along with the gasket and start the engine. Exhaust should come out of both exhaust ports. Whichever port that has no exhaust is blocked.

Refer to post 68 in the supplied link to clear the exhaust port.

http://www.benzworld.org/forums/w163-m-class/1535734-air-injection-system-diy-7.html#post4370875
 

·
Registered
2004 ML 500
Joined
·
6 Posts
Thanks. I have both diverter valves out, and will check for exhaust from ports when I get home this afternoon.

I am not having any luck finding BG products though. The local distributor's site says the do not sell through retail channels. Are people just asking to buy cans at their local garage?
 

·
Registered
2002 ML500; 2007 BMW 335XI
Joined
·
410 Posts

·
Premium Member
02 ML320 06 ML500
Joined
·
16,982 Posts
Thanks. I have both diverter valves out, and will check for exhaust from ports when I get home this afternoon.

I am not having any luck finding BG products though. The local distributor's site says the do not sell through retail channels. Are people just asking to buy cans at their local garage?
Find a distributor nearest you.

https://www.bgprod.com/contact-us/distributor-locator/
 

·
Registered
2004 ML 500
Joined
·
6 Posts
Finally ran the engine with the diverted valves opened up. Steady exhaust pulses from both sides.

The air pump runs when 12v is applied directly, now I need to make sure it runs via diagnostic tool.
 

·
Registered
1999 Benz ML430, 1997 Benz E320, 2006 Toyota Avalon, 2002 Jag. S-Type (sold), 1985 Benz 380-S
Joined
·
153 Posts
Finally you are getting into diagnostics instead of reloading parts gun. :)

Find in your area who carries BG products. You are looking for BG 211 Induction System Cleaner.
From Dollar store get plastic funnel. Measure stem on air injection valve and get something close. Cut funnel so it fits snug into air injection port in intake manifold.
From computer store get attachments for regular household vacuum cleaner that are used for cleaning around computers. You need to get something small enough to fit air injection port.

Using piece of wire (coat hanger) try to brake loose any visible carbon deposits in air injection port. Keep area under constant vacuum. Whatever brakes loose needs to get sucked out and not go down the passage. Passage is cast into cylinder head so it is very rough. Once all visible carbon is out put funnel into port and pour about 100cc of 211. If funnel fills up and nothing goes down let it sit overnight. It will slowly creep down and open the passage. Go slow and don't overdose. You don't want liquid to enter cylinders. You may end up with perfectly clean air injection and bent rod.:mad: To make sure there is no liquid in cylinders turn engine over by hand (ratchet with socket) at least two revolutions.

After overnight treatment reinstall all back together, warn your neighbors, fire department and start your engine. Let it idle with air pump on. There will be very high amount of noxious white smoke.
Hi Witek_M, your instruction you gave back on 10-02-2010 for a combustion cleaning using BG-211 I have a question. Should you apply the BG-211 through the air injector valve stem while it's still in place, or should you remove it from intake manifold and apply the BG-211 directly into manifold where the valves connect to manifold? I hope I got the names right...thanks again
 

·
Registered
Dallas, Texas
Joined
·
7,122 Posts
Hi Witek_M, your instruction you gave back on 10-02-2010 for a combustion cleaning using BG-211 I have a question. Should you apply the BG-211 through the air injector valve stem while it's still in place, or should you remove it from intake manifold and apply the BG-211 directly into manifold where the valves connect to manifold? I hope I got the names right...thanks again
You need to remove air injection valves and try to remove any carbon while things are still dry.
 
141 - 160 of 169 Posts
Top