Hi All

I've been working on a flood damaged S550 2011 for about a month. When I got the car it was in a sorry state. I managed to free up the engine and it turns smoothly when cranking with socket and breaker bar, had water in a couple of cylinders. I hope it did no lasting damage internally. Transmission electronics seem OK, again I don't know at this point if there is any damage.

Have replaced all the following ECU's in the car and also changed all the CANBUS Distributor blocks and new CAN plugs into those blocks where old plugs were damaged.

CGW Gateway
Drivers Side SAM
REAR SAM
ABC ECU
AIRBAG ECU
Drivers Seat ECU
Passenger Seat ECU
REAR Left and Right Door Modules
Command head unit with dvd changer
Air conditioning ECU
Automatic truck closer
Amplifier in trunk
Combo Sirius/HD Radio
Media Interface
Teleaid Unit
Central Control
Central Display Screen
Parktronic ECU
All Ballast and ECU's in headlights

Most of the units have had SCN coding performed online. Seats are still out.

Star Diagnostics indicates at last that it should be clear to start. BUT when I turn the key... NOTHING. No clicking, no voltage drop. Could it be starter or alternator, or would motor electronics inform me of this. Not sure if its even calling for the fuel pump???

I've attached some screenshots, can happily upload more, just tell me what to do

I really need the experts help here. I'm OK with modules, wiring and stuff like that, but don't know much about engines at all.

I'll gladly send $200 via paypal to the person who's suggestion makes this baby fire up. Have saved plenty buying ecus from ebay and in europe etc. Plus this should make it a bit of fun for people who are always so helpful anyway.

Please give me your input and suggestions as to what to try.

Thanks

 

do you have fuel pressure at the rail?

Whats the voltage of the battery?

I'd want to see if I'm getting 12v to the starter with the key turned.

alternator shouldn't matter at this point.

 

Will check fuel at rail in the morning

Battery is new and fully charged

Will also locate starter (right rear I think) and stick a meter on it whilst turning key.

Will report back with results. (starter could be water damaged, water came up quite high all round but did not reach top of engine, ECU seems untouched)

 

Pm me.

 

What would i do Is test the voltage when the key is in, and see if voltage changes ..I would diss assemble the ignition unit just so I can test if its giving any voltage at all . Or see if you can paypass the ignition system by hot wiring the car . Iam sure it's not easy but with the right electric schematic it should not be very trouble, since you have the ignition unit out .

I don't know what state you are in ,but there is a lot of unemployed benz expert mechanic that can come to your place and do the troubleshooting ..will at least in CA .

 

Will test voltages tomorrow. Am in Vero Beach, FL.

 

OK Starter was very rust (blurry pic below) so I assume it may be shot.

The big wire had 12v constant. the smaller wire only had 10v when cranking. Is that too low? Is that enough to even turn the starter? (Battery was fully charged)

Am off to pick up another starter now.

Fuel pressure at the rail was fine.

 

that starter looks fubar, definitely replace that.

 

UPDATE: Got another starter today, looks identical but perhaps half an inch longer from an SL550 but supposedly fits

will try it in the morning

 

UPDATE:

Engine is finally running. Big thanks to E55greasemonkey and Shifter who gave me lots of advice via PM. I paid them $200 between them for their help and am very grateful for the advice, they both know their stuff :-)

Still have problems that hopefully someone can help with. Car has heaps of white smoke coming from exhaust even after running for a while. (pictures attached, looks like something out of wacky races) Star Diagnostics says its misfiring on cylinders 1 and 8.

Did a compression test and results are below
1 60 psi
2 80 psi
3 80 psi
4 80 psi
5 80 psi
6 80 psi
7 80 psi
8 60 psi

Could have just said compression was 80 on all except 1 and 8 which was 60 :-)

Is it normal for compression to be so low on these big newer engines? Bearing in mind this vehicle was flood damaged, when I got it, there was a little water in 1 and 8, so I'm guessing rings may be rusty. I removed all plugs and puts heaps of marvel mystery oil in them (not sure if relevant but 4 of the 8 cylinders are holding the oil steady, including the 2 with bad compression, other cylinders its passing down below.

Am hoping and praying the engine is OK else the car will no longer be a reasonable cheap deal, I have almost 30k in it so far, most electronics are now fixed, have not driven it yet so not sure about transmission.

All thoughts and advice appreciated as always.

 

If it don't work out and if this are 20" wheels I'll buy them..

 

80psi of compression is garbage. Do you have a very weak battery?

Motor like that should make at least 190-200psi consistently in each hole. Is the gauge a decent one? Is the connector screwed together tight?

something ain't right here.

 

OK I admit the tool may be not the highest quality, got it from harbor freight yesterday :-)

battery is good. I guess I will buy a better gauge to get more accurate numbers.

any other suggestions if the mystery oil does not work? I guess I should wait and see first.

 

That's not good. Compression is low on all cylinders. I would expect to see around 150 PSI or so. Unless that gauge is junk, but regardless the smoke is concerning. I would suggest looking into the cylinders with a borescope to see if there is any scoring on the cylinder walls. If so, a used junkyard engine would be your most economical repair option. I also noticed your suspension is sitting way too high..maxed out, actually. This car has air suspension so something is wrong there. Could be as simple as corrosion in the level sensors.

Also make sure you flush the transmission fluid ASAP if you haven't done so already.

Look in star diagnosis for a compression test..I believe this model year has that available in the SD software. Look under "guided tests" The computer will monitor the flywheel speed while you crank the engine with the gas pedal to the floor (to let air in) . This is done with the spark plugs installed..Don't worry- it will disable fuel and spark for you too.

 

OK thanks again for the decent advice. I was really worried about the low numbers so just hooked up my trusty harbor freight US General compression tester to my E350 2011 which runs perfect. The result 80 psi, same as the other 6 cylinders on the s550. So it looks like the gauge may not be as top notch as I thought, I guess you get what you pay for.

I did see a compression test option in SD today, did not go into it but will try that tomorrow.