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So, one day, about a month ago; our Mercedes ML500 gave us a bit of a scare while towing a spyder VR4. It shot out some transmission fluid out (possibly the vent or wiring harness connector) and made us a bit paranoid as it was sitting at just over 200k miles. Well, I got it towed back to the shop and did a trans fluid and filter change and all is good again. But, Emilie was freaking out that we don't necessarily have another family back up car in our arsenal. Although we are borrowing her mom's minivan, we'd like to give it back because I don't want to fix all the crap wrong with it. So, Emilie goes on a hunt for what she wants.... a sedan/wagon. Mainly because parking in NYC is expensive for an SUV, so she wanted something cheaper to park. Well, what we ended up with may be even more expensive to park than an SUV .

Behold, our ebay/craigslist deal. A 2005 Mercedes S600. There are plenty of other trim levels of the S class that would be totally acceptable to just about every other human being on the planet.... except for Emilie. She finds a model she likes and she wants the damn top of the line (although there is an S65, but that's out of my price range). This beast is powered by a 5.5 liter V12 biturbo engine. It produces over 500 hp stock (underrated so AMG model would be more powerful) and over 600 lb-ft of torque. And it's only RWD. But, the kids can't be late!

As you can see.... the ML500 is having no issues. Especially considering this car weighs 4500 lbs and the ML towing capacity is 500 lbs .



Now, we got this thing WAY under the normal value of these cars. So, of course there is a major flaw. But, in the grand scheme of things, it's minor.







Someone must have pulled an insurance job and cashed out on this guy. Every panel is cut up on it. All of that beautiful hand stitched NAPA leather . But, it's time to dive into the mechanicals first. Brawn before beauty! First thing was first. This had 2 engine codes for a misfire (something we knew about before buying it). It's a common issue with these cars. Generally remedied with replacing a coil pack. That may not seem like a big deal. But there are only 2 of them on the whole engine. Each cylinder has 2 spark plugs, so each coil drives 12 plugs. They are also $1400 each (or rebuildable much cheaper). So, I scan this thing and see cylinder 3 and 11. I think to myself "shit, that's both banks"... aka, both coils. I start on cylinder 3 and find a spark plug gapped totally shut. I regap that guy and scope the cylinder. All is well in there. So I put that side back together and work on the other side. Cylinder 11 has the wrong damn spark plugs in it! They are gapped too high as well. I think I hit the jackpot. So I regap them and switch them with plugs from another cylinder to see if the problem follows the plugs. Sure enough, as my luck would have it, it stays on cylinder 11. This bank has a brand new coil pack on it already. Problem is, the wrong plugs. They burned out the coils for that cylinder. Repairing it can cost between $130 and $275, so it shouldn't be too bad. They are also a lot easier to get to than one might imagine.



I've also fixed a couple of small issues with it. The driver side headlight did nothing. So, I had to remove the front bumper in order to address the issue. It really does help if they actually plug the headlight in. That's all it was.
Also, the switch on the driver front door would not operate the driver rear glass. I popped the switch panel off to find 3 cut wires. Slap them back together and it works just fine.



There are a few more wires that are cut throughout the car. So, I'm waiting on a factory service manual to arrive to help me trace everything. The door locks don't work, trunk doesn't auto open, and the privacy window shade in the rear doesn't roll down. They are all tied together in the same circuit, but I need the diagrams to help pinpoint the issue.

I already have a new water pump, heat exchanger pump, accessory belt, belt tensioner and idler pulleys, spark plugs, and fluids/filters to do. Then I'll work on other stuff. After it's all sorted, a nice ecu/tcu reflash will be in store. It will bump it up from 493 hp to a low low 620 hp... oh, and around 700+ ft-lbs of torque. That will still allow the kids to be late to everything!

First night working on it, I got the new IC/Heat Exchanger pump installed. This one is a little bit of an upgrade from stock... but the same size. The stock ones are a known trouble spot and are well undersized. This upgrade is still a bit on the "too small" side, but it wasn't a bank breaker and it was available right away. Better than a broken one.



The old pump was totally shot. But, that's probably because the IC system had no fluid in it. And that is probably the reason why I smelled a faint coolant smell when we got the car.



Going through some of the electronics, I find this gem. There is a refrigerator option. Once the car is sorted out, I may be hunting one of these down. They are kinda small, but would be nice for the kids on a long trip.





So, after I got side tracked with the refrigerator, I went on to diagnose an electrical issue. None of the door locks work and the trunk has to be opened with a key. No assist on it. And the doors don't "soft close". There is a vacuum pump inside the car that does all of these features. That pump is shot. But, the parts car will have one.... so hoping it's good. If not, they are around $200 for a used one.



Pump got a little hot on the ground side of things.



I had pulled the pump apart to check the impeller (which is also a common fail point on the motor). All seemed ok. I think the motor is just shot. There can be an issue with an electrical contact on the circuit board that can make the pump run non-stop. That's probably the case with this one.



Some maintenance stuff came in today. Just to put the amount of spark plugs in perspective.

Scored a parts car off of the Copart auction for a mere $1400. Getting the parts car off of the trailer was a fun operation... especially since Emilie arrived to the garage with it when it was dark out . I stole the wheels from the other S600 to throw on this guy in order to get it off of the trailer.



I got the air pump from the parts car and installed it into the other one. Now the door locks, head rests, and trunk function like they should. I grabbed the ignition coils from the parts car and installed the driver side one onto the good car. Still showed a cylinder 11 misfire. So, I'm pulling injectors to clean them out and reseal them. I'll swap cylinder 11 injector with cylinder 12 to see if the misfire follows. Also doing valve cover gaskets. These guys are pretty damn long! But, the engine does look clean for 107k miles.



Swapped out the plugs on the driver side of the engine as well. Old vs. New.



Cleaning out the injectors using an ultra sonic cleaner and some degreaser. There was some build up on the injector filters, so I'm hoping a good cleaning fixes that.



I ripped out the intercooler system to make it easier to work on. Dealing with the valve covers while the intercooler system was still installed made for a bad time.



Wheels and brake calipers are going out today for powder coat. New tires, brake pads, and rotors are on their way. I should have the wheels and calipers back tomorrow (hoping).

New tires arrived for the S600! 245 fronts and 265 rears. Someone put some el-cheapo 245's all around on it that were mismatched.

The bolts that hold the ignition coil cassette are notorious for stripping out... as is just about any other threaded boss in the valve cover. So, I used some Timeserts to rethread the holes. Hopefully no more jiggly ignition coil cassette, intercooler, and intake box!





This is the hole that is drilled, counter sunk, and tapped to receive the timesert.



This little timesert that shouldn't strip ever again.



And that little bugger installed into the valve cover. 6 holes in total were repaired. 3 other holes were just cleaned up with a tap. Tomorrow I will get to the other valve cover.

So, more things happened to the car. First, cleaned the damn injectors hoping to fix that #11 misfire.

Before



After (with all new seals)



Then it was time to tackle the job I dreaded the most.... the water pump. You basically have to tear off the front of the car to do this.



Got the damn serpentine belt out of the way. It was 1 tooth short of a 6 tooth belt that it is supposed to have. Some numb nuts installed it wrong and it shredded off one of the teeth.



Then Mercedes wants you to use some special $275 tool to get the crank pulley bolt off. So, I spent 3 hours making 3 different holders.... which all failed .



Tool attempt #1



Tool attempt #2



No pictures of #3, but I was sure it would work. Instead, it failed. So, I had to remove the radiator, ac condenser, suspension cooler, power steering cooler, and heat exchanger in order to use my impact gun on the bolt. Viola!

After all of that, it's all back together with new pulleys, tensioner, belt, and water pump.



I got the whole nose back on for the first time in what seems like forever!



Then, comes stripping the parts car. Now, I usually do all of this stuff at night time (working until as long as I can). But, doing the parts car strip outside made that not feasible. So, I stole my one mechanic and we spent the day stripping this hooker.









Car is back up and running better than ever! No more misfires, and purrs so nice. I guess when you just throw the whole parts bomb at it, it's bound to work! And,we got some cool parts back from powder coat. I couldn't let Dan be the only one with purple bits. Although these are going on a woman driven car .











I would have mounted the tires to the wheels, but I was sent the wrong TPMS valve stems. So, I need to call my place up tomorrow to get that fixed. Then, all that is left is a couple of front suspension bushings, bleed the brakes, inner fender covers in the front, swap in the new interior, and a detail! Plenty of time to accomplish that before Sunday!

Oh, and after firing it for the first, second, and third times; I had like 5-6 cylinders of misfire codes come up. Car ran like total ass and I was about to kick the shit out of it. After clearing the codes for the 3rd time, I figured I would just rev the shit out of it before it came down to settle on an idle speed. After that, it ran smooth as could be. I guess it just needed a little help

Half the pictures wouldn't load for me.

Coop

hah you are such a glutton for punishment.

You have all the fun for us, Hans.

I'm hoping to throw it into dyno mode today to see what it puts down. Once I get back from vacation, I'm hoping to work on a tune for it.

You move quick! Now fix all the bad links.

So, got back to working on this turd because I'm tired of looking at it and not driving it. The battery ended up taking a dump. I replaced it with a new Interstate AGM battery ($225) and now I don't have any more errors and my trunk closes properly. Go figure! It's also seemed to gain a little bit of power. I'm guessing this battery just couldn't handle the draw. It's a super high amperage draw on this thing. Just connecting the battery for the first time and I saw almost 20 amp draw right away. I can't imagine what the draw is while starting the car and powering up all of the on board computers, but I'm sure the lack of power of the battery contributed to some errors.

Traction control now works perfectly. With it off, you can still do a burn out, but it's very controlled. It's like a low speed burnout .



I brought it over to Moto East and got it aligned. It was so bad, I had to eye ball an alignment on the car before I could even take the 1/2 mile trip to their shop. I'm willing to bet the front toe was over 15 degrees out.



The initial readings from my eye ball alignment. They were pretty spot on!



I had my mechanic drive it (since he has an inspection license and it's not inspected yet) and it is pretty smooth. I do have some new hydraulic suspension components to install which should help with the ride as well. They have these 4 accumulators in the system that are pressurized. They are basically a pressurized fluid reservoir and supply fluid on demand. If the pressurized sack in the accumulator bursts, then the fluid just fills the whole thing with no static pressure pushing on the fluid. This can cause the suspension to feel a little bouncy. The life expectancy on those is said to be around 80k miles. With 107k on it, I'm sure they are original and probably shot.



Also, with the battery having died, I think it took out my main gauge cluster as well. It's a common issue and easily rebuilt. Right now I have the cluster in from the parts car so the odometer doesn't read anything.

This thing is pretty beast. With the traction control "off" but still active in the background, you can get it sideways in a turn. But, it's almost as if it's a very controlled motion. Really weird feeling. If I put it in dyno mode, I'm sure I'll wreck it .

Next up is to install the rebuilt suspension valve blocks (just new o-rings on some solenoids that tend to leak over time), new accumulators, and I need to figure out the hard start problem it has if it's left to sit overnight. It loses fuel pressure and takes way too long to start. Could be fuel pump or injectors. I will probably start with a pump and filter and then work my way to the injectors.

That's pretty cool. I'm not surprised changing the battery made such a difference.

I'm still really tempted to swap out the one in my car. Ever since I got it back from the clutch repair, it's been cranking slow. The battery checks out on O'Reilly's battery tester, and the car shows a full charge on the MMI display. None of the modules are throwing any voltage codes. But something still isn't right.

The battery is a flooded, CarQuest brand. It's barely 2 years old. But I don't know what else it could be.

Damn overly complex German cars...

I had mine on my Snap on battery charger over night. It would show 100% when I would go into work in the morning. Then it just wouldn't even crank over the first time trying to start the car. This battery was OEM and 7 years old, so it got its use out of it.

Started working on the paint until I get a lift free'd up so I can finish up some of the suspension work. The hood was pretty shitty. I went over it quick with a buffer and realized that it would just be easier to wet sand and buff it, so that's what I did.









I also got the trunk buffed out. It was pretty much the same as the hood, but I didn't wet sand this part. It's small enough to just hit it with compound instead. The trunk also got a new emblem. I'll try to pull the license plate bezel off and see if my PDR guy can push out that little dent by the S600 emblem.



The roof is in crappy condition too. I'm really not looking forward to buffing that part out. It's a really long roof!

Damn. Nice work. I really, really need to learn some basic polishing. Vira's cars need it something awful. My Audi isn't in spectacular shape either.

Old paint is super easy to buff and very forgiving (if it's base/clear). The exact opposite if it's single stage. Check out 3M's Perfect-It system. That's what I use with great results.

I've got a red 2G hood and one of the dented fenders from the Spyder. I should practice on those. I'm 90% sure they're clear coated.

If not, it's not like I'm a stranger at the junkyards

You'll know right away. Generally the 3/S cars red color is single stage. But, once you start buffing and you see red on your pad, you know it's single stage.

Buffing is pretty easy. I watched a few random videos online before I bought my Porter Cable DA buffer.

BTW I did this by hand

Before:


After: