Hello,

I have a check engine light on my car. I brought it to a German car specialty shop and they troubleshot everything. I received 3 estimates. One of the 3 is to repair an oil leak that the car has (this is not causing the check engine light), however I'd say it is the most important issue in need of addressing and that is something I refuse to do my self. It was also the least expensive repair, so I am fine with letting the shop do it. One of the invoices seems like something I can do myself (I am a marine and power sports tech and mechanical engineer, therefore I have the knowledge/experience to perform simple (albiet pain in the a**) repairs). Here are the invoices. I can definitely source the secondary air injection pump : https://www.aliexpress.com/i/2251832...apt=4itemAdapt

I am looking for the Air Injection Check Valve both left and right. I keep finding this and I have a suspicion that this is the check valve, but I don't know for sure. Can someone confirm? https://www.carpartsdiscount.com/aut...l?3593=1873310

If not, does anyone know where I may be able to source this part? Is it possible to get it (both left and right side) for < $100.

The second repair estimate: it calls for replacing the entire intake manifold just for a small flap within it that has malfunctioned. They said it was stuck. I believe this is beyond my ability as a tech to do myself and would gladly have this done at the shop. The problem is that apparently you cannot buy said flap separately without buying an entire intake manifold. Does anyone know if there is any way possible to procure said flap?

Finally I have to get the oil leak fixed, but I will ask the shop to do it since it is relatively less expensive ($600).

Please see the repair estimates below. If i can source the flap for the intake manifold, the shop said they will install it, but also claimed it's nearly impossible. The shop says that this problem is so common on these cars that they've done this job a million times. I am currently trying to find a job (just graduated with my BS in ME), so my money is very tight, yet I need my car to get me there once I find one. Therefore, what is reasonable for me to do myself, I will. Maybe you guys know something we don't? Well, I appreciate any input you may have, so thank you.

 

Is there emissions testing where you live? What model is your ML? I'm assuming 350 gas? Where is the oil leaking from? The only common place is the centrifuge cover and that's an easy DIY. I've got two ML350's, one with 191k and the wife's with 90k miles. And a third ML63. I know everything about them. Maybe too much.

 

Sadly yes, we do have emissions and they are very strict afaik. As for where the oil leak is coming from, according to the quote, the main job is to replace the oil cooler seal, so that must be where the leak is coming from. The car is a 2011 ML350 4matic gas. The biggest issue I have with the car is that I have no clue where the wheel lock key is, and so I cannot remove the stupid lug nuts. They have the flower shape. So if anything requires wheel well access, I dont think I can get to it. I am thinking of having a mechanic take then off and replace them with normal ones.

 

If it helps, this is the oil leak invoice:

 

You don't have wheel locks, those were standard lug nuts for a time from MB, they can be removed with a 6 point 17mm socket IF the caps haven't been rounded out, or you can buy the flower socket on Amazon or Ebay. The problem those wheel bolts had is corrosion between the stainless flower cover and steel bolt would cause them to swell.
The oil cooler is an easy DIY if you have the place and the tools to work on it. I'd suggest replacement of the belt, tensioner and idler pulleys while you're there as the idlers can fail leaving you stranded.
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​​I'llanswer in more detail later as you can see I'm struggling with my phone

 

Wow you are really amazing Mr. Monkey! Yes so I watched this video and it is excellent: . I'm a bit worried about the circlip though, is it a snap ring? Or is it just a clip that i can installed by hand and remove with a 90ish degree scribe? It's in a location that I will only be able to feel and not see. Usually with snap rings, you need to be able to see so that you can make sure it is properly in place given the dangers of snap rings. Clips are much easier to deal with and i should have no trouble feeling around, because they can be removed and installed with just a scribe, or flathead or sometimes even your hands. Also do i need to bleed the coolant system/ Power steering? I can get the gasket for about $5, some fluids, the belt and I suppose the pulleys as well if they are not too much and I can afford them. I have tons of tools from my powersports tech days, but there is a naval base near me that will rent me a bay for $6/hr, and provide me with any tool i need, so I will use that to do the work. I plan on doing it in mid June since I am going on vacation for my graduation at the end of this month. I am just trying to plan now. Since I feel it is the most important job, I will do it first.

As for the wheels, I suppose my verbiage was wrong. Yes I have those flower lugs. I once was planning on going down that route for a brake job, but after my research into a tool, I found that the flower lugs on these care vary between each and every car and that I would need to remove all of my lugs and get a tool that pairs with each special lug (based on what you are saying, it doesn't seem like this is the case, and I hope that it is not). I once had a Ford Edge that had a special lug in each tire that required a keyed adapter. Since i didn't have the adapter, I was still able to take the lugs off by hammering on an oversized socket and zipping it off with an impact. I do worry about stripping the flower sockets though. I am either inclined to get the proper tool, or tbh I'd rather just buy normal lugs, bring it to a shop and have them zip off the old ones and put on the new normal ones. What is your recommendation? I definitely dont want to strip them (i'd probably need plasma to cut them off if i did and who knows what else would get warped/damaged in the process. I really don't want to replace studs/wheel hubs/steering knuckles).

I would like to try to perform the work detailed in the secondary air pump replacement quote, the only issue is, I am unsure about the check valves that are described in it. I wish they would put the part numbers but I guess I can call MB to ask for them. Hopefully that will get rid of my check engine and I will be able to pass inspection. If it doesn't then I have no idea how I would do that intake manifold job on my own because I do not want to buy an entire intake manifold. It seems like such a waste being that I am sure there is nothing wrong with the one I have on there except for possibly the flap.

 

The clip is easy, start it loose prying with a flat blade pocket screwdriver then a large screwdriver to slide it completely off. To install, start it by hand then push it all the way with a prybar. This is a good time to replace the seal and resevoir as there is a filter inside which clogs over time. You bleed the cooling system by filling it and running the engine and defroster. The steering can be bleed by filling and with the wheels off the ground turn the steering back and forth 20 times. You'll still have some trapped air to deal with when you start the engine.
There are repair kits to fix the manifold, it still has to be removed. However the flaps inside can break off and end up inside the combustion chamber or wedged in a valve, this is very bad! You can buy a new Pierburg manifold for $600-ish they are the oem manufacturer for MB. Reinstalling can be tricky as the gaskets are thin and fragile. The manifold will not set a check engine light, just a stored code. You can manually open the left and right flaps from the lower front of the intake and leave them that way forever if you wanted, you'll loose a little torque or HP.
Sounds like the shop wants to change the entire air injection system, to avoid a comeback which is understandable. You probably only need the pump, maybe a switchover valve, or you just have cracked vacuum hoses. Hard to say without diagnosing it myself. Does the electric pump run on cold start? If not, maybe replace the pump first and see of the code doesn't come back, you'll have to clear it with a scan tool.
Buy some regular wheel bolts without the flower covers.