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So... just replaced my passenger side coil, cleared DTCs and decided to start the car and let it idle for a bit.
After about 20 minutes, got a code on my reader P0410 air injection pump. Rut roh... did I frak up a vacuum line somewhere? No CEL though. Also, it's 30F outside and the car hasn't been driven in a while. Condensation perhaps?
Regardless, can anyone kindly tell me where the secondary air pump is located on an M275 along with its relay?
I keep reading posts that state I should hear the pump come on when the engine is cold. People state it sounds like a hair dryer. I don't recall hearing anything like that on my S65. I wonder if the pump is even functional.
Well, I'm going to pull the passenger side airbox and rotate the intercooler out of the way again this weekend to have a look at the vacuum lines. I know that they're made of hard white plastic inside a black sheath. They tend to get brittle over time. When replacing these lines, is it OK to use standard rubber vacuum lines? If so, anyone know what size; i.e. ID/OD of tubing?
If anything got messed up during removal and installation of the coil pack, it's one of these; most likely the top vacuum solenoid that goes to the check valve. The bottom solenoid has a T line that goes to the turbo.
BTW, does anyone know the part# for the relay? Also, what relay sockets on the fuse panel can I jump to test if the pump is getting 12V?
Last edited by amstel78; Feb 27, 2017 at 01:30 PM.
Another question... what is this that's circled in red in the photo below. I started thinking to myself after reviewing the photos that there should be a vacuum tube connected to that, but there isn't. I won't have access to this until this coming weekend, but it'd be nice to know what that rubber plug/sleeve is at the end of the check valve. Is it just a plug, or a vent to air? Or is there something supposed to go there?
When I was moving this stuff out of the way during coil pack replacement, I was very careful not to stretch or move those vacuum assemblies too much for fear of just this thing happening. Guess I wasn't so careful.
Don't have an answer to your question but in the second pic the two vacuum lines that run across the passenger valve cover to the front cross each other and you can see they then get flattened by the airbox. When I did my plugs at 120K I replaced those lines just to make sure there weren't any issues. Just a FWIW.
Don't have an answer to your question but in the second pic the two vacuum lines that run across the passenger valve cover to the front cross each other and you can see they then get flattened by the airbox. When I did my plugs at 120K I replaced those lines just to make sure there weren't any issues. Just a FWIW.
Randy
Thanks Randy. Did you replace with the thin hard vacuum line that MB uses, or did you just swap out with flexible rubber lines?
Out of curiosity, do those thin hard lines just pull out of the rubber sleeve that's attached to the solenoid or are they glued in?
Also, FWIW - I tested my air pump this morning. Fuse and relay check out fine, and when starting the car, I can hear the whine of the pump. It runs for about 20-30 seconds then turns off once idle drops to normal.
Thanks Randy. Did you replace with the thin hard vacuum line that MB uses, or did you just swap out with flexible rubber lines?
Out of curiosity, do those thin hard lines just pull out of the rubber sleeve that's attached to the solenoid or are they glued in?
Also, FWIW - I tested my air pump this morning. Fuse and relay check out fine, and when starting the car, I can hear the whine of the pump. It runs for about 20-30 seconds then turns off once idle drops to normal.
Local dealer sells the vacuum line so I used exact same stuff but made the line a little longer and ran it up along the top of the valve cover so they wouldn't get smushed again. Reused the thin protective cover. The line is not glued into the fittings and will pull out. I think I used some pliers and twisted them loose. My fittings were still very pliable even at 120K miles.
Local dealer sells the vacuum line so I used exact same stuff but made the line a little longer and ran it up along the top of the valve cover so they wouldn't get smushed again. Reused the thin protective cover. The line is not glued into the fittings and will pull out. I think I used some pliers and twisted them loose. My fittings were still very pliable even at 120K miles.
Awesome! Thanks for the information. Will pick up some of that line from my local MB dealer. I believe they charge about $6 bucks a meter.
I was able to get OE MB vacuum line and replaced the one going from the diverter valve (vacuum solenoid) on the passenger side valve cover to the check valve at the front of the engine. Please confirm if my terminology is correct, and that saucer like device with air and vacuum hoses coming out of it is indeed the check valve.
Unfortunately the error still comes back. So, I'm thinking it could be the diverter valve or the check valve as the secondary air injection pump does run. As my WIS/EPC computer is at my home in PA and I'm currently in Manhattan, can someone please give me the part numbers of both valves? My vin is WDBNG79J56A477014.
BTW, how long is the air pump supposed to run when the car first starts and the engine is cold? In my case, I can hear it come on and then it'll shut off perhaps 20-30 seconds later, or slightly after RPM dips down to normal speed. I'm assuming that's normal?
Any help to the above post would be most welcome. Specifically trying to identify the check valve on the M275 as it pertains to the secondary air injection circuit. Thanks!
There are probably more of us who have this problem i bet. With a Mighty Vac I have checked the front two aspirator shutoff valves from the vacuum line "Y" to the valve and it holds. going the other way at the "Y" I get no vacuum. I now have to trace that direction. I'm going to try some sort of smoke test. By the way, I have changed the check valve at the front of the manifold (grey valve), no change.
There are probably more of us who have this problem i bet. With a Mighty Vac I have checked the front two aspirator shutoff valves from the vacuum line "Y" to the valve and it holds. going the other way at the "Y" I get no vacuum. I now have to trace that direction. I'm going to try some sort of smoke test. By the way, I have changed the check valve at the front of the manifold (grey valve), no change.
Is the check valve the round thing at the front of the engine, closest to passenger side, that has vacuum lines running into it? It should have a rigid vacuum line going from the vacuum solenoid located on top of the passenger side valve cover?
Think I found my problem. There's no vacuum going to the diverter valves. Looked behind the engine and noticed that the vacuum line going from the manifold to Y32 switchover valve was broken. It's completely disconnected.
It's a tight fit there though. Any suggestions on best way to repair? I'm afraid of moving the other lines; don't want to break those during replacement of the line going to Y32.
P.S. Can anyone with EPC check to see if there's a part number for the rubber Y connector shown in the photo? Many thanks.
Yikes - doesn't look like fun! I don't have any issues but need to go look at my car. Looks like a shot from the passenger side? Keep us posted on the repair.
Yikes - doesn't look like fun! I don't have any issues but need to go look at my car. Looks like a shot from the passenger side? Keep us posted on the repair.
Randy
Yes, it's by the passenger side. I'll have to remove the airbox. Not sure if I can manage with the intercooler where it's at, or if I have to move that as well. I hope not, because I can only pivot it upwards. If I have to remove the intercooler, then that means having to bleed the IC system again which is not fun.
Truth be told, I was actually relieved to see that broken hose. Sounds strange right, but after months of not knowing what the heck was wrong with the secondary air injection system, this hose while probably a PITA to replace, is at least a relatively straight forward fix.
Yes, it's by the passenger side. I'll have to remove the airbox. Not sure if I can manage with the intercooler where it's at, or if I have to move that as well. I hope not, because I can only pivot it upwards. If I have to remove the intercooler, then that means having to bleed the IC system again which is not fun.
Truth be told, I was actually relieved to see that broken hose. Sounds strange right, but after months of not knowing what the heck was wrong with the secondary air injection system, this hose while probably a PITA to replace, is at least a relatively straight forward fix.
I do not know whether you fully solved your problem, but if you do not hear it come on then likely same problem I had. I was dealing with intermittent p0410 code and finally found out there is a huge fuse in the passenger side fuse box. Its orange. It was very hard to see where it was broken but sure enough it was. Bought new fuse and no more code ever since. ( think its a 40 amp orange fuse)
If that doesn't work then look at air pump relay and see if pump turns on. if not then you have bad air pump.
As to your vacuum lines, I replaced my entire vacuum system including all plastic rubber and hose clamps. Everything was beyond brittle. Be very careful if you repair with intake on as two of those vacuum lines go to a dashpot underneath intake manifold. If the dashpot cracks, you would have to remove your cylinder heads to replace. I suggest you try and replace your whole vacuum system as you are seeing one problem and more are likely to show up with broken vacuum fittings.
Last edited by MooksM275; Jul 3, 2017 at 09:14 PM.
I do not know whether you fully solved your problem, but if you do not hear it come on then likely same problem I had. I was dealing with intermittent p0410 code and finally found out there is a huge fuse in the passenger side fuse box. Its orange. It was very hard to see where it was broken but sure enough it was. Bought new fuse and no more code ever since. ( think its a 40 amp orange fuse)
If that doesn't work then look at air pump relay and see if pump turns on. if not then you have bad air pump.
As to your vacuum lines, I replaced my entire vacuum system including all plastic rubber and hose clamps. Everything was beyond brittle. Be very careful if you repair with intake on as two of those vacuum lines go to a dashpot underneath intake manifold. If the dashpot cracks, you would have to remove your cylinder heads to replace. I suggest you try and replace your whole vacuum system as you are seeing one problem and more are likely to show up with broken vacuum fittings.
Hi Mooks,
Pump is good. So is the fuse and relay. I hear it come on every time I start the car and the engine's cold.
I'm pretty certain the vacuum connection is the issue now. I checked this afternoon, and I have vacuum at the Y-junction in front of the blue check valve that I showed in my earlier photo. I was fortunate enough not to have the vacuum line break off inside; it seems to have just slipped out. There was no vacuum at the other end of Y32 going into the two circular diverter valves, which is why I think I'm getting the error code. The ECU isn't detecting any change at the O2 sensors because the valves aren't opening and the added air from the pump isn't getting pushed down the exhaust runners in the head.
What is this dashpot you referenced in your last para though? I've been in that area several times already; you can see one of the other photos I posted earlier when I was replacing my coil pack. The only vacuum line connector that I had to be careful with was the one attached to a bracket which is bolted to the frame holding the transformer. There's a line going from that into a sensor attached to the passenger side IC.
This is the one:
Other than that, the only other vacuum related things are those two solenoids clipped on to the valve cover and lines going to the turbo actuators.
Ok so if the pump is turning on then yes its likely that you have vacuum leak. You can test the circular diverter valves as well. Apply a handheld vacuum pump to the feed and look inside to see if valve moves. Sometimes (on older cars) they get stuck.
FYI-The vacuum coming off intercooler and going to sensor-that is the MAP sensor and when it fails you do not get a check engine light you just get reduced power.
The dashpot is underneath the intake manifold between the v of the cylinder heads. It stores vacuum so that the system operates seamless when switching the diverter valves, boost pressure control valve etc. There are vacuum lines that run underneath the manifold and connect to this dashpot. The only way you could see it is to remove intake manifold.
I had my manifold off and could replace these rubber vacuum hoses underneath. I will tell you that they are prime to crack over time and will cause issues. May be a nice project for you in the future.
In this picture, the dashpot is number 280. Again, it is not the vacuum line going to the intake in the back-it is a separate canister between the v. AS you can see, the vacuum coming from the dashpot affects the changeover valve that controls the Smog Pump circular diverter valves. If there is a crack in any of these lines, it could be causing an issue.
Number 280 in this diagram.
Last edited by MooksM275; Jul 4, 2017 at 10:37 PM.
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