Ok I look forward to hearing coz this is a royal pain in the arse lol.There's a lot to go here, I'll go onto more detail later. Although Snapon kit is not much use on a Mercedes, we will do what we can.
A Honda please Arudge don't swear at me again, it's not polite! Lol.Firstly, the alternator warning lamp on the dash, this ties in with the voltage reading of 14.18V on the Snap on device. This voltage reading is a little low, we should be looking at 14.40V leading me to suspect poor earth connections, possibly the main engine to chassis earth strap or poor connections on the battery posts. It could be a faulty regulator within the alternator but dropping just 0.2V smells more of poor connection to me. Earth straps do fail, you can't clean them, the problem is within the crimp itself, you can only replace them.
The P codes offered by the Snap On device don't seem to correlate with Mercedes P codes so we will just run with the text descriptions.
Crank Position Sensor.
Always something to worry about. They usually just drop dead leaving you stranded at the roadside. The CPS controls the entire ignition system and without it you have no ignition system. The do fail and in my experience have a 10 year life expectancy, if yours is dying it would certainly give you misfire, but normally they just drop dead leaving you with no engine. They often work again when cold only to die when they get warm.
Fuel trim.
Your fuel mixture is all wrong because.............
Manifold pressure
Your fuel mixture is all wrong because.............the manifold pressure is wrong because you've got a leak. I know it says pressure but it really means vacuum. It becomes pressure when the supercharger comes on line. Remember, at low rpm the inlet manifold is under vacuum as the engine draws air, the vacuum turns to pressure as the SC starts pumping air. Either way, the map sensor on the manifold isn't seeing the pressure it expects to see. Some would say the sensor is faulty, i'd say you a have a leak. Could be a loose pipe or connection, there's lots of them. On mine there's a vacuum operated valve that allows air from the manifold to the exhaust system to superheat the exhaust on startup, they stick.
Then there's the cam chain and it's adjuster which can screw everything up.
I've had all of these issues on mine and good few more. I suspect your misfire isn't just one issue but a collection of issues, all of which are common to Mercedes.
I know it's not what you wanted to hear, and only a STAR diagnostic can be more accurate. You may be better off with a Honda!!
Andy Rudge
Ok got ya! So If the codes ain't cleared even if the sensors have been replace and the issue is resolved when started the engine would still run like crap unroll codes are cleared?Clear codes after every change you make. Some codes won't go away till you have three successive long runs (a long run being a certain number of minutes at normal temperature) and that will also mean the light may not go out.
Why Can't U live nearer to me! LolFaults will clear down 1st time with a star machine unless it’s a current fault.
No.Also will a star be able to tell me electronically if there is a vaccum leak?
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Ok right so that's a lot to deal with!The loom.
Sorry, i forgot about the loom. The oil in the loom is another Mercedes issue and as Star pointed out, is restricted to the engine bay with the most damage done when it gets to the o2 sensor, the oil contaminates the sensor and ruins it. That would throw a code of it's own. The oil originates from the cam magnet and there's a fix for it, as again Star has mentioned.
I had oil in the plugs and it causes problems as LK has described, yours look clean so they should be ok.
However.......
You have a CAN error. Controller Area Network. This is a high speed digital network that connects the various ECU's together. You have a break in the network which is almost certainly a dodgy plug, again we are looking at corrosion or oil contamination. I don't know what information is carried on the CAN line in your car, but i'd put it high on the list of things to sort out. The CAN line is easy to spot in the loom because its always a twisted pair. So if you see two wires twisted together that's your CAN line. There twisted together to reduce outside interference. I think the CAN line starts at the ignition switch and covers items like the ignition, abs, traction control, climate control and stuff that needs lots of data from sensors.
Vacuum testing.
I'll cover this later.
Engine warranty.
If it starts, runs, doesn't bellow smoke that's as much as you can expect.
Many thanks Andy.. I'll be sure to check every plug and connection to see what's there.
You can see the oil in the left connector block and the corrosion in the right block. This is what we're looking for.
Yeah I agree the star is definitely the way forward! Dose anyone know or recommend someone around the RM10 area?A STAR machine and a skilled operator are worth their weight in Gold. The depth of analysis is incredible but it's not a cure all, but it will save you a lot of time, and i think this job is going to take a lot of time.
No it never showed CPS, it only showed a multiple misfire!I'd be more concerned about the crank position sensor. Did the crank position sensor show on your mates basic reader?