speed7

I wanted to get some feedback regarding an issue I'm currently troubleshooting.

Car info: 2006 C55 94,500 miles.

Symptoms: (This is going back almost a year)
When cold and has been sitting for more than 8+ hours.
Under decel at very low speeds the car acts as if you turned off the key. This only happened at most 3 times within the past year. Always under that condition.

New symptoms:
Did it when the car was warm after driving to work (10 miles) on the freeway at a constant 70mph. (I wanted to make sure I stated that the car was at proper operating temperature.

Stopped at a coffee shop and got a coffee then continued to work.
Same driving habbits as before. Under decel at very low speeds (I'm in a parking lot leaving the coffee shop) car dies.


What I've done so far. Since the car died early in the morning when cold a few days ago. Then the next day while the car was warm it died I took it to my mechanic. He found no information in the computer regarding any errors.

So he pulled the crank positioning sensor and saw it was the original one that came with the car. As he stated the "old part number". He did a test against it by heating it up and testing its OHMS resistance while warm. He stated that it only got up to about 1600 OHMS. He recommended we replace it since it was the old part number. But he also stated that a failing part would reach or pass 2000 OHMS.

He also was busy that day and was nice enough to actually look at the car (He's one that you have to make appointments 2 weeks in advance). But wanted me to make sure the car took the new sensor. Since he didn't have time he wanted me to calibrate the new sensor. This is where I got a little confused. He said for me to take it for a drive. And while in 3rd gear give it about 1/2 throttle up to 4000 RPM. Then let off the throttle. He said to do that 2x's. I did this.. but I don't think I did it well.

Next morning during warmup the car died. Then the next evening after driving home I stopped for gas. Again the car completely warm. While driving home a few blocks from the gas station in a residential area. Only doing about 25mph.. More like 22mph come to a turn and let off the throttle and the car dies. I think it died at about 10mph since it was a 90 degree turn.

SOOOOOO..... he my mechanic did suggest I try my spare key and that's where I am now. So far the car is fine but its only been 15 or so hours since it died last night.

Any ideas? Does anyone know about the calibration of a new CPS? And if so should I try calibrating it again?

I can do the parts and replace game if needed.. however I'd really like to do new sway bars instead of needless parts. BUT I do need to get around... So priorities.. dying engine comes first.

LILBENZ230

I haven't heard about such calibration.

Have you cleaned or replaced the MAF?

speed7

No but that's a really good idea. Low RPM's and light on the throttle means not that much air coming in... so if its starting to go...

Anyone have the part number for that for a C55? I want to order it ASAP from getmercparts.. they take awhile but its cheap!

speed7

Did a quick search its 113 09 40 048

speed7

Also from the same thread:C 55 idle surge/stall fix!

https://mbworld.org/forums/c32-amg-c...stall-fix.html

From SoCalC55:
Took the car back to the dealership and after a couple days of searching the result was "Clean Throttle Plate, Found Throttle Angle High At Idle, Remove And Clean Throttle Plate"

I was told that there was an excessive amount of carbon buildup which was causing the car's computer think I was traveling at a higher speed then I actually was. It would then tell the engine to take in more air and would stall out the car.


This was also mentioned by my mechanic as a possibility. So I'll investigate that and/or have him clean it.

Thanks for the help! Your post actually may have fixed this. I'll post the results in the next few days.

speed7

ORDER PLACED! $310 plus shipping... Bye bye H&R front sway bar till payday. =(

SunnyRayToronto

Did you use Mercedes-Benz OEM CPS?

What happens when car stalls? Are there any warning lights displayed on the instrument display cluster? Did the car coast to a stop? Did you notice the front radiator (cooling) fan spinning in high mode like a turbine engine?

Did you get OBD2 Scancodes read? Did your mechanic hook up the car to Mercedes-Benz STAR Diagnostic System to read the error-fault codes?

speed7

My mechanic only works on mercedes cars and only uses OE Mercedes parts.

He hooked it up to the star system and found all of my error codes. There were a few. But nothing that seemed related to the engine, ignition, or fuel pump.

The car does coast to a stop. But the fans aren't spinning out of control. Or at all if I remember. It's almost like the car was tuned off. And I'm not remembering any lights on the dash.

After the MAF replacement of I still have an issue I'll clean the throttle plate.

IF there is still an issue I'll buy a go pro and get a video of what happens.

SunnyRayToronto

Hopefully, your mechanic also cleared all your error-fault codes so that next time there's a reading he won't be looking at old codes.

So your car coasted to a stop,... by itself? And you never applied the brakes or anything? Was it like a had brake type stop or just like a gradual stop that you usually do at a traffic light?

When your car stalls? Is it more likely to happen when its on an inclining slope?

If it happens again, keep an eye on your instrument display cluster for any Visit Workshop messages,.. especially from ESP Visit Workshops, Engine Visit Workshops and Coolant Visit Workshops. And open the windows to listen for the front radiator (cooling) fan.

Has your car been regularly serviced and is up to date with regards to all recommended maintenance,.... is the transmission oil also regularly serviced?

speed7

Yeah he cleared it all but also printed it out and gave it to me first.

Regarding the coasting.. I'm moving and have to stop the car with no power. Mainly because I can't start it until I'm in park again. Up until last night the fastest I was ever traveling was maybe 2-5mph. Last night I had to make sure to stop the car with no power steering or brakes.

Every time it has been on a flat surface. I live in the bay area on the peninsula.. its pretty flat around here.

All service records are up to date... I keep the car in tip top condition and don't like to skimp on needed work.

Thanks for the suggestions. I'll make sure to keep an eye on the cluster and visit the workshops you mentioned.

SunnyRayToronto

If you don't apply the brakes when the car stalls, it'll probably stop itself,.... its like it shift itself to a lower and lower transmission gear.

Yes, I would agree go with CPS, MAF (try cleaning first), then throttle body in that order.

When a car stalls, the Coolant Visit Workshops likely get triggered because front radiator (cooling) fan isn't getting the signal it was expecting. ESP Visit Workshop also likely to trigger since the signal was lost. Front radiator (cooling) fan is likely to spin in high mode like a turbine engine because it's not getting a signal from ECU - front SAM and spinning in high mode is its default (to protect the engine from overheating).

Do you usually do a lot of stop and go city driving or is it more top speed highway type driving? The reason I'm asking is because the carbon buildup could be a result of lots of stop and go city driving,.... these cars need to get on the highway once in a while,... the high speed will help burn off the carbon deposits and all the other junk that accumulates in the engine.

speed7

I'll try letting it coast next time if the opportunity presents itself.

I do a mix.. mostly highway but also in traffic so I don't consistently get to go above 55mph. However on a regular basis you can catch me doing 80mph on the way home for 10 or so miles.

Also for the last month or so I was driving it like a baby since I needed to do the front brakes suspension and motor / trans mounts. As of Sunday all of these issues are now fixed. The last thing I did were rotors and pads for the front. Now I'm back to properly driving the car and not treating it like its a delicate piece of china. =)

SunnyRayToronto

I doubt I'll be able to catch you doing 80mph,.... especially since California Highway Patrol haven't been able to yet,....

If it happens again, head straight to your mechanic to get it hooked up to Mercedes-Benz STAR Diagnostic System and get the error-fault code read.

Keep us up to date on your progress and what works.

speed7

Thanks.. yeah that was the bummer about last time.. no faults or error codes in memory. If this keeps happening I'll see if I can borrow the Diagnostic system for the weekend and driving with it hooked up. Then pray that it happens... but then again.. I hope it doesn't get to that point. I want the MAF to fix the issue since I just spent $300 bucks.

SunnyRayToronto

I assume that $300 was for a new MAF along with the cost of labour to install.

Often a good cleaning of the MAF and area around it with commercially available MAF cleaners (like CRC SensorKleen) can fix MAF issues. But then again, a new OEM MAF along with professional installation ensures that its done right.

speed7

That's a new OE not OEM MAF from getmercedesparts.com

I'll be doing the work myself.

For a consumable part like this I'd prefer to just replace it. I understand there are cleaners but it does have 94k on it so might as well replace it. If anything if its not the culprit it is preventive maintenance in my book.

LILBENZ230

The car will not apply brakes to stop itself. Also, a stall doesn't automatically trigger the cooling fans. I think that was a problem specific to your car. We have plenty of stalls reported on the forum but no one ever mentions the fans.

You should be able to start the car in Neutral, but you cannot start it in drive of course.

SunnyRayToronto

When a Mercedes stall, not only does the engine stop but also various subsystems shut down as well (power brake, power steering, gas pressure, etc,...) which could trigger a bunch of visit workshop messages because all the sudden the ECU/front SAM are not getting the expected response from the various sensors,... heck the instrument cluster lights up like a Christmas tree! When the car stalls, if the front radiator (cooling) fan doesn't get a signal then it will go into its default mode and it will automatically start spinning in high mode like a turbine engine.

Speed7,.... since you already changed out your CPS, clean out the throttle body BEFORE you install your new MAF. Clean out your throttle body and intake with Sea-Foam Spray (use supplied long plastic tube to spray past old MAF),.... and also use Sea-Foam Motor Treatment,.... this will help clean out all the carbon and crap. Note: Sea-Foam is NOT on Mercedes-Benz list of approved fluids,... that list includes Chevron Techron,... but Sea-Foam should do a much better job (search for forum). After using Sea-Foam, after you've gone through a couple tank full of gas, its recommended you do an oil and filter change.

Oh,.... good idea to record your MPG before and after the Sea-Foam.

speed7

Thanks Sunny.

Yeah I've heard of sea-foam before. And I've heard some pretty good stuff about it.

I actually have yet to have another stall. At the recommendation of my mechanic I am using my spare key. I've also canceled the purchase of the new MAF for now. And if it does come to needing one I'll be sure to purchase it. However I will also clean the parts you mentioned as well first.

Question though why the comment about recording my MPG before and after? What would I be looking for other than a performance loss or gain?

SunnyRayToronto

Sea-Foam will get rid of the carbon buildup and sludge clogging your engine (Sea-Foam Motor Treatment) and intake (Sea-Foam Spray). By getting rid of the carbon buildup and sludge clogging your engine, intake and fuel injectors; your engine should run a lot smoother and you should notice a good improvement in MPG. Who know,... after using Sea-Foam,... your MPG might be so good that you'll post it in your signature like LilBenz230.

speed7

Heh... well I have a C55 soooooooo mgp or performance will most likely lead to my rear tires being consumed more. =)

Yeah I think I get at the very best 21mpg on the freeway. Usually 19... An extra mpg wouldn't hurt but no way will I get to the miles per gallon as you 230 owners.

W210MB

Hi Everyone.

I have a mercedes w210 CDI 2001 model.I had a breakdown with intstrument cluster, then I changed, but it is show up'' Steering gear oil Visit Workshop''.
I looked for fluid everything is OK. Fluid does not spend, no leak. I have changed fluid, but still is show up this sign.
Can someone help me about this please?

blkonblkc55amg

I am having similarproblems as well inmy 06 c55. I;ve relaced the primary fuel pump on the passanger side of the ar already because it was nt sending fuel to the left side of the tank(driver side) i noicedi was having problems first when the fuel level was no moving at all no matter how much driving or fuel as put in and the car stalling when at low speeds. Now this morning oddly enough almost a month after the repair the car stalled on the about a dozen times on the drive to work. All th stalls happened in stop and o traffic at normal operating temp. but what made this time different was after starting the car back up an trying to drive off the car shuttered like it was cutting in and out of power which its never done then the check engine light came on and everytime i was come to a stop the car was jerk real hard downshifting to a stop then stalling again. any thoughts?

speed7

That sounds a lot more violent than my issue was. Mine wouldn't stall or shudder.. but rather just "turn off". No last gasping for air as it died... just would give up.

Good news if you had the check engine light come on. I'd read the code first and start from there. Really sorry to hear about your car man. I know what its like to have a broken ride and its not fun. Good luck and let us know what the check engine light is erroring out on.

speed7

Oh and I'm not sure I stated what the solution for my issue was in this thread. I replaced the cam positioning sensor. Fixed it right up. Even canceled the order for the new MAF.

The C55 has been running like a champ since this fix.