Hello Guys,
I'd take any help I can get figuring this out. I have an 07 S600 that I love so much, I have daily driven it for 3 years plus now, and I have kind of maintained it myself over the years, there aren't that many trusted mechanics in my corner of the world, plus I haven't had any major issues beyond my DIY capacity. I have just done a bit of work on it sorting out the list below:

• Coil Pack (RHS) from V12icpack
• Spark Plugs
• Motor Mounts
• Transmission Mounts
• Fuel Pump
• Fuel Filter
• Air Filters
• Water Pump
• Aux Water Pump
• Coolant Tank

Apart from the coil pack everything else was from fcp euro. I did all four struts earlier in te year.

A little bit of back story, before this last wrenching, i had replaced the right coil pack and Voltage transformer after I had misfire codes on all right bank of cylinders, and everything worked fine, i went out for an evening drive on a Sunday, nice easy and wonderful experience, until i rolled to a stop at the traffic lights, the car went off on it's own, i restarted it and then it started misfiring, I plugged in the scanner and again same right bank of cylinders were misfiring, i limped the car home, pulled the coil pack and voltage transformer sent them back to V12icpack, they checked and confirmed the coil pack was fine but sent me a new replacement regardless, the Voltage transformer however had moisture in it and had failed. They are backed up on order for this and I'm expecting a replacement unit any day now.

But here is the issue, after installing all the new parts, the car would not start, it tries to start and then dies immedialtely more like it's not getting fuel, i have cheked the new fuel pump and filter again and they are confirmed working, could a bad voltage transformer cause this? I had thought it would at least start but run rough/misfire badly. I should alos add that the car had been parked for about 3 months as i had been out of town, I did the installation when I returned last week.

Is there anything I should check, maybe something I have overlooked? Is it possible i'm not getting good fuel pressure? (Unfortunately, I don't have a fuel pressure tester adn i'm not sure i can get one around here, but is there a crude way to check?)

Than you very much for the assistance.

 

The trouble is that just about any sensor could also cause your car to start up and then fail once a reading is missing at the ECU. You're going to have to scan it and read the fault codes. You're pretty much guaranteed to have one or multiple. Is your scanner good enough to read MB specific codes?

 

Pull codes.

 

if u can afford a v12 and a coil pack and transformer - you can afford (and as you elude to - with no local support - need) decent diagnostics, if keeping this car and or other merc - the benzninja deal could be the right choice - dealer tools and an expert to help out when stuck

CPS cranks position sensor ?
Checked fuses on the new voltage transformer?
Remembered to re-check and plugged everything back in ? I did some work on my father's a while back and after double checking what I'd done, it was going mental and upon a third check somehow a sensor I was sure I'd clipped home - wasn't plugged in correctly ...

 

Thanks for the response Guys, The only engine codes are the misfires, nothing else.

I have an Autel Mk808bt, I was going to get the DS 900 or the SDS but the last update I did on the MK808 came with a huge difference, as I am now able to do more most notable of which is the suspension, I can activate rodeo test, run calibrations, etc.

Maybe I should get the SDS then?

 

did you come across this bit.... its what I wrote having spent an evening reading and watching that guys videos of what goes wrong...

the iron core inside each of the 24 OEM coil sticks breakdowns with time (not mileage), often randomly with any of the 24 coil sticks dying around the 11 year mark, as this fails the windings short, and can send voltage spikes round the system that often blows the brains out of the voltage transformer and or the whole banks coil pack. So one ageing coil stick starting to breakdown, starts a chain of events introducing the possibility of three major issues

its quite an odd get up - rather than a coil on top of each plug with its own 12v power supply like the V8s get - the V12 mercs have "two coils sticks per cyl" that swap duties back and forth each spark. One spark its being a 180v main coil, then next spark its an emission clean up spark coming fractionally late to the party as a 23v coil. To achieve the magic spark fest, each bank of 12 coil sticks are part of a complex electronic circuit broad making one banks (6 cyls) coil pack.

so the issue usually starts with an owner exercising the car, which makes life harder for any of the coils, and that often brings in a random one cyl coil stick failure. But that can blow the whole coils packs circuit board taking out all 6 cyl on one bank. And or blowing the brains in the separate voltage transformer - this VT is what gets the required 180v / 23v power supply change. Thus one coil stick starting to age, often ends up giving a two or three cyl misfire as the voltage transformer gets damaged.

However even with good coil packs the voltage transformer can get cooked to death from normal engine heat over time and bring down the whole set up in a costly disaster

Usual senario one coil stick ageing can bring down the whole lot, and even when the whole 12 stick coil pack on one bank is replaced, a damaged VT (caused as the first stick dies) often ends up killing the replacement coil pack and its a circle of expensive hell and head scratching

so the fix is three opportunities for a mortgage

remove your voltage transformer (VT) today and exchange it for one of his upgraded longer lasting overhauled VT OEM boxes now with two fuses you can replace - to stop a complaining coil stick sending back a spike and blowing up the Merc OEM $800 VT unit

then if brave and stupid you can buy a faulty coil stick on ebay and likely trash the whole bank trying to fit one new budget fake coil stick for a cyl you identify as playing up, OR swap out the whole group of coil sticks (made in house via china) with his upgraded coil pack where all sticks have been replaced and re-soldered carefully to the refreshed circuit board

alternate option replace the OEM VT and fit his upgraded remote located (for a cooler location) more sophisticated VT box which I guess can cope in solid state with coil sticks throwing teddies and you don't need to play swapping fuses in the rain at the side of the road...

Allegedly the VT, both coil packs, and a set of 24 spark plugs - at circa $7k - should be swapped around the 70k miles and or every 7 year mark


https://www.v12icpack.com/

 

So I also have Clark's coil packs on both sides and the older style upgraded voltage transformer. I kept the old OEM VT as a spare. I ordered his new VT which is mounted on the fender rather than on top of the engine. I am a big fan of his products. But I also encountered a no-start condition on my 2007 S600 and we ended up going back to my old style VT. I don't have any misses at all but for some reason it won't start with the new VT. Works fine on the old VT.

It is an expensive decision, but you might think about an OEM VT (on top of the engine and see if the car starts). Clark is really great and he is obsessed with quality control; so he will eventually figure it out.

You really need to pull codes. Keep us posted.

 

Clark is indeed WONDERFUL! An interesting experience on your end, I have both the coil pack and VT from Clark, water/moisture found it's way into the first VT somehow, I mounted mine beside the engine battery - he has been super supportive and is sending me another unit, I have plugged back the old one that mounts on top of the engine which "used to start the car at least".

I guess, at this stage, I'll wait for the replacement to arrive, I'll test that and if it doesn't work, I'll try to go OEM and in the interim, I'll find a way to lay my hands on a more powerful scanner and pull codes.

I will keep everyone updated on developments.

Thanks a LOT everyone, I value the essence of the community.

 

@BOTUS, thanks a LOT for the insight and yeah I had come across that bit of information when I was trying to decide on OEM packs or not and that's how I came by Clark at v12icpack, I got my coil pack and VT from them. They have been super supportive with great attention to detail just like @vettebk mentioned.

 

the point vettebk makes about the updated VT stopped working is enlightening - sounds like merc invented a trick to cause issues no one yet understands...

mounting the VT beside the battery... the windscreen drains on the 221 are some of the worst ever invented, they block up and all the filth from the screen over spills (I suspect the sunroof drain also comes down the pillar to spill over too), I need to remove the battery and its holder - I suspect I have lots of leaf litter hidden underneath, eventually it will take out the HVAC fan.... when I had the ABS sensors replaced they deliberately don't re-fit the grommets to allow for a bigger better drain from that area - to let everything else escape where the screen drains failed to cope

 

Crank position sensor failure - can cause no start issues - and the stumbling and stalling as you slow to rest (eventually if you keep using the car an engine light flickering can come in to play - but its hard to spot as you are trying to cope with a loss of power steering and maybe funny brakes - its a very common wear item on cars - particularly Mercs) and reasonably cheap and easy to do (needs an inside out E torx socket) - the heat in this area on mine took out the multiplug - this "pin bush housing" is a part they can get inside 3 days and better than having a dodgy connection. The retention clip fell off as I tried to remove - three days later when I had the new bit the whole housing basically crumbled as I went to replace it. The plastic bit is only $3 order BOTH (sensor and pin bush housing)

part 906 PIN BUSHING HOUSING
CRANKSHAFT POSITION SENDER UNIT 2-PIN COD.B;SLK2.8;L5;TO A2751501333,183 001 A 16 854 530 28 - $2.55
https://nemigaparts.com/cat_spares/e...asis=22117663V






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