My E55 is running very rich and I’m not sure why. I’ve had different answers from almost everyone I’ve taken it to. I ordered cats to put on it because it ran fine before the previous owner bought it with mods already installed, cut the cats off, slapped e63 mufflers and an x pipe on it (3 owners, mods done by the original owner will be in picture attached). I was told by the muffler shop that it will only make it worse and I need a tune (figured some back pressure wouldn’t hurt?). That’s being said I still held off and have just been letting it sit and borrowing cars. It had a eurocharged stage 2 tune until I put it back to stock map 2 weeks ago which didn’t really do anything. I paid eurocharged $700 for a tune just to be told they don’t log A/F ratio on their software, after it did nothing of course. I’m now hearing a sucking noise, almost like a vacuum leak coming from the right side below the oil filter housing. It stumbles on idle and when I give the slightest bit of gas (intermittently). It’s down on power and pouring black smoke. It still pulls hard and can get up the road but I’ve not really ran it hard either out of fear I’ll be out of a daily. Any opinions welcome just need some kind of direction before my car gives out

 

Sounds like a vacuum leak. Why not fix that first than report your results.

 

I would but I have no clue where it’s coming from. I’ve looked from every angle and I can’t find where the noise is coming from. Maybe the supercharger gasket. The entire reason of this post is Bc I don’t know where it’s coming from or what my tuning issue is. It wasn’t hissing like this before but it still blew smoke.

 

You can use a smoke machine or spray carb cleaner. if the RPMs go up when you spray an area with carb cleaner, you've probably found the leak. Otherwise you can pressurize the intake tract with a smoke machine to check for leaks.

Edit: Carb cleaner is INFLAMMABLE. be extremely careful and only do this on a COLD engine, with a fire extinguisher nearby, and spray tiny amounts at a time. Better off using a smoke machine.

Or take it to a real mechanic instead of throwing money at it on tunes or cats.

btw cat would have never fixed anything if it is running rich, because the fault causing richness has already happened in the engine. The only thing a cat will do is clean up the exhaust gasses somewhat.

 

The thing that comes to mind near the oil filter housing is the vacuum tube/hose that makes its way from there to the back of the supercharger next to the throttle body. The metal tube there has been known to come out of its grommet so check all ends and clamped connections on that line as it transitions from hard pipe to rubber line to hard pipe again. About as thick as a pencil.

But yeah if nothing obvious a smoke test is the logical first step here.

 

Car is currently with a mechanic for some ball joints so I’ll tell him take a look at it before he gives it back to me. I’ll report back any findings or take a look myself if he finds nothing. Smoke machine is something I’ve been told but I have 2 questions. Where do I feed the smoke into the engine. And do I need to make my own or are they sold somewhere that I’m not seeing.

 

Smoke is fed into the supercharger/plenum, best spot is one of the vacuum nipples on the top rear of the supercharger. Remove the intake Y and tape up/seal off the throttle body inlet so that everything is sealed.

Many mechanic shops will have a smoke machine if they do a lot of diagnostic work, but single mechanics might not make the investment. You can Google making your own, I did years ago and made one with a $10 soldering iron, a mason jar, an old sock, and baby oil and it worked quite well. Definitely felt sketchy though.. the expensive ones some shops have have pressure control etc and are ideal, but if you make your own just plan on using your lungs to blow through gently, don't use an air compressor and blow something out.

 

I’ll ask him when he gives me a call back. I watched a couple videos and they were all slightly different but the same concept. I just don’t feel comfortable putting an air compressor to a pickle jar.

 

So I picked the car up 2 days ago. When I got home I noticed a small amount of smoke coming from the passenger side in the engine bay. (The car has had some smoke come up on startup intermittently but is usually barely enough to see.) but this time I had a good 10 second cloud of smoke that finally dissipated. Not sure how my car deteriorated that quick while at the shop but I’m assuming they gave it hell so never going back there and will be doing my own work from here on out. I was going to do a valve cover job when I got the car back anyway but seeing that made me order parts immediately. Went on fcp euro and got everything for the gasket job. I went ahead and ordered some spark plugs since I’m already in there as well as an OEM oil filter which leads me to the original problem. When I did the oil change I bought the recommended filter from auto zone (my first mistake). I knew it didn’t look right. Returned it and found the closest thing which was Mann before reading that even the Mann filters aren’t correct because the o rings don’t seat properly. So could it be the o ring is not sealing the filter housing and I'm getting some air past it? After I change everything out I’m still going to
smoke test it but i’m hoping it’s not from the slight over-torquing. (I’m not sloppy, it was a stupid mistake and trust me i’m not proud of it) I’ve done lots of car work but never to something foreign. I didn’t think about measurements in Nm instead of ft lbs, I just read the number 25 and tightened. No cracking or anything like that and as soon as picked my phone back up I read it again, loosened it and retightened it to 18 ft lbs. assuming that did no damage and the replacements go well, the smoke machine will be the true test for air leakage. If I have a question during any part of the process do I open a new thread or continue to post on this one? It seems pretty straight forward from reading but I’m sure I’ll have one that can’t be googled. Thanks to all.

 

Your oil change has nothing to do with the vacuum leak sound that you hear. Still need to smoke it first.

 

I also just re-read the first post - is it correct you still have mods like pulley, headers, and injectors but you flashed a stock map back on? You either need to keep a tuned map on it for those (especially injectors) or revert mods back to stock before thinking about diagnosing power and rich running conditions.

 

Exactly what I’ve been wondering. Okay i’ll get back with Eurocharged after the gasket/plug job and see if they can get another tune going on it. They’ve tried twice but to no avail (at least it’s free). Hopefully sewing up those issues will get me in the right direction. I have 2 questions, First is tuner preference. Does anyone recommend against Eurocharged? I’ve heard mixed things about them and been told to try Fabtech but I don’t want to spend another $500-$700 on a tune without some other opinions (assuming I’d need a TCU tune as well since the car has one now). Any other tuner recommendations are welcome. Second pertains to the intake system. I’ve seen a lot of debate between FTP, VRP and NeedsWings for these aftermarket intakes. I’ve been looking at them because I know Eurocharged tunes run rich so I’m thinking if it gets a bit more air it will compensate for the rich tune?And how would the stock vacuum lines hook up to it? I’ve never seen pics of the back so I’m not sure if it has the same inlet that the stock system does. I thought about DIYing it with aluminum piping and heat wrap as it would almost cut the price in half but I can’t do that without advice from someone that has/had one installed or built one themselves. Also want to add that I’ve looked into a larger throttle body as well but I figured the intake would do a better job of getting more air in.

 

That’s very reassuring. I’m going to source the parts to build one tomorrow so I can have it before I begin the repairs on Thursday. Probably gonna go the Scotty Kilmer route and use a paint can. Seems safer and more efficient at producing smoke.

 

Tuning - Eurocharged is pretty well respected on here, the general consensus seems to be either choose between them or Tony at RaceIQ. I run Tony's map because he tunes well with the fixed pulleys too, but I don't think jumping ship from Eurocharged to someone else is going to fix any issues. Yes, off-the-shelf tunes run rich just for safety as every car is a little different, but not rich enough that it causes you a noticeable problem like smoke etc. The most you'll see is some sootier exhaust tips and a slight reduction in MPG, but if your car is running pig rich there are issues deeper than a tune most likely. It really should be scanned for codes on a Mercedes diagnostic tool, OBD2 won't pick up anything until it sets a check engine light, but there can be other codes in the specific modules that won't set a light. For example, a bad Intake Air Temp sensor reading the temperature as super low could cause an over-rich condition, bad MAP sensor etc.

TCU - Don't even worry about that now. The TCU is completely separate and will not affect how the engine runs, and you can run different tuner's tunes on TCU and ECU without an issue unless you have some super weird setup, different diff gears etc.

Intake - I'd also say don't worry about that now. The stock airboxes flow enough for your mods, aftermarket won't add anything (and the ECU would just adjust anyway) and I've heard of more problems with those intakes than benefits. Namely the silicone couplers collapsing under heavy load causing very rich conditions, and additional heat from the metal (factory plastic boxes don't get as hot). They are an expensive sound increaser and engine bay dress up item, but you're still feeding all that air into a single throttle body.

Throttle Body - You'd definitely make more power going to a larger TB, but they don't just bolt on. The supercharger needs to come off and the snout either machined wider or replaced with one from an SL, or some of the aftermarket MBH/VRP options etc. The power is pretty much guaranteed, but there is a not-so-small chance the car will run worse as it can trigger some of those underlying codes and cause the ECU to revert to a backup map (not tune-able) and the car can run dangerously lean. You may not know without a wideband, so I'd never recommend upgrading TB without the proper datalogging and monitoring equipment.

So, to sum up if it were my car - get a properly scaled tune on the car for the mods, perform smoke testing to track down the noise/smoke etc, and get it on a Mercedes STAR scanner, or at least get a CarSoft MBII or similar to scan the actual engine computer for Merc specific codes. If you've got no maintenance history, you may want to consider things like the Intake Air Temp sensor, MAP sensor (although a pain to get to), and front A/F sensors as those can all have impacts on improper fueling.

Good luck sir!

 

Sorry for they late update, had a lot going on but finally got to finish everything up a few days ago. Found the vacuum leak without smoke testing after scrolling through some forums. Turns out it was the small metal pipe that runs under the driver side surge tank, which is apparently a common issue after changing the valve cover gaskets (job was done by pervious owner and I assume he never checked to see if it was reattached) so I removed the surge tank cover and re inserted the pipe. I was told the car had step colder plugs but when I pulled them out they were the stock plugs. Can’t remember the part number but I know the stock plugs have a 6 and the colder plugs have 7 and the plugs I pulled out had the 6 on them. I went back to eurocharged tune, Put the colder plugs in, changed the valve cover gaskets and did both breather covers which are a real pain to both remove and prepare (especially in 30 degree weather, had to set up a tent and a space heater to get the gaskets to cure). I
believe the engine is pretty much buttoned up but I have one issue that has really put a damper on things. When I torqued the bolts down to only 11 nm
(recommended is 15-20 so glad I didn’t do that) one snapped and another snapped my T-30. Seems to be common as I read a couple threads about people snapping their bits due to their torque wrench not clicking so my next job is removing the surge tank once again, extracting the bolt and finding a replacement. I can’t find any online so if anyone has a suggestion on where to find them it would be much appreciated. If not I’ll have to take the 2 broken pieces to a hardware store and find one that fits. I’ll also be swapping to BC coilovers because my right side shocks are leaking due to a pretty bad pothole. Roads in Statesville NC are absolutely horrible and I knew it was a matter of time before something like this happened. If anyone is interested in the left (or even right) side shocks or the compressor I’ll be selling
them on the classifieds to make a little money back on the swap. So the bolt that I broke off and the passenger shocks seem to be my only issues at this point, but I will post an update soon on how the engine is doing in a few days. So to sum things up I need the bolts for the surge tank (image shows the specific bolt) and some advice on why it’s riding so rough. I’m hoping it only damaged the shocks and did nothing else because I’m getting terrible vibration and I cant pinpoint the exact component (praying it’s not motor mounts). Will the shocks cause this or does it sound like a different issue. This happened before I tore into the engine but it wasn’t sagging this bad until now. I’ll replace the ball joints while I’m in there but as I said about the bolts any Input is appreciated. Thanks guys.

 

Haven't checked with MB? From the parts catalog 000000-002047 M6x80 (should confirm the length as there are four differnt lengths) retail $4.00. Good luck.

 

This may be a stupid question but would it be bad do drive it about 15 mins to work and back until the part arrives at the dealer on Tuesday, don’t know why that wasn’t my go to lol only $11 for both sizes. I don’t want to do any more damage but I’m supposed to be giving the persons car that I borrowed back to them tonight and I’ll have to drive something.

 

I wouldn't worry about that short of a drive, its mostly or all sealed with the other bolts, and if it did cause a vacuum leak it would far less than the hose/pipe that was leaking and you fixed.

 

Okay good. I’m replacing it as soon as I get the bolts but I didn’t order them until Friday evening. Thanks man.

 

So I checked my codes and all I can say is wow. It’s showing 6 fault codes on the ECM screen. Each code is listed below:

•P2089 - Camshaft Position Actuator Control Circuit High bank 1

•P2010 - Intake Manifold Runner Control Circuit High Bank 1

•P2083 - Exhaust Gas Temperature EGT Sensor Circuit Intermittent Bank 2 Sensor 1

•P202B - Reductant Tank Heater Control Circuit Low

•P20D4 - Exhaust Aftertreatment Fuel Injector B Control Circuit High

•P20A2 - Reductant Purge Control Valve Circuit Low

I’ve read about each individual code online and I can check all of these things but all of these at once make me fear it’s an issue deeper in the vehicle. I could be wrong though so I would love to be corrected because I don’t have the money to pay someone to replace internals. Any recommendations on what to do next? I bought this car thinking it was in perfect condition but don’t we all. I also started getting a slapping sound, almost like a knock but not as severe (don’t think it’s piston slap or anything but I’ll upload a vid if it starts happening again). I assumed it was injectors but it’s seems a bit more intense than that, it’s intermittent though.