Hi, I've been chasing the problem for months now.

Problem: Car shuts down while driving, while slowing down or driving at constant speed or stopped at traffic lights. Once it stalls, I restart the engine and everything is fine, No codes or anything.

Solution: I thought that the Torque convertor or lockup clutch could be casing this at slow speeds so i replaced oil/filter. But when the car stalled in Neutral I knew this wasn't the problem.

Next I looked at the CKP crankshaft position sensor, checked the resistance and it checked out OK, I also had it on STAR and the CPS and CKS checked out ok.He said the waveforms were ok, but I might chage this part out just to be sure (CKS)

Next I was thinking I might have a bad ground somewhere because, car was in a crash with damage to right hand side. I checked battery voltage and terminals and everything looks ok.

When this problem happened initially it was a once off and now if I drive 2 miles down the road it will stall a few times, sometimes it takes a few seconds to restart.

Ive had the car to Mercedes and an Indie and they cant find the source of the problem. (there was no code at this stage)

Then today when I was driving the engine cut and it gave an engine code.

I have a cheap OBD-II scanner at home and I read the code:

P0607: PCM/ECM (powertrain/engine control module) has failed.

I am wondering is it a problem with my ECM (are they called SAM units on mercedes???) or am I getting that problem because of something else?

I dont even want to know what a new ECM and coding costs.

Is there anything esle I can do, anyone seen a problem like this before?

Any help much appreciated

Note: I've had my DPF removed and whatever software goes with it and I am running the Swirl motor resistor mod. Could this have anything to do with it?
Thanks
Charlie,

Car is 2008 S320 CDI, I'm in ireland, but car has the same engine/ setup as .

 

Hi thanks for reply,

DAS Xebtry, is this STAR? Can this be used to Code ECU?

I have a crankshaft position sensor ordered from mercedes costing €40, its cheap so i'll replace this tomorrow and hopefully this will fix the problem,

If this doesnt work I'll bring the car to the lad wit the DAS, and see what he can find.

If it is the ECU, can I use a second hand ECU and have him code it? Also does the ecu have to be the exact same or can I use one from a ML or a Sprinter which use the same engine?

Thanks again

 

Just plugged the car again using my OBD scanner to check fuel pressure:

fuel pressure at idel 760rpm is 3400-3500 PSI. when u crank the engine it jumps to 3900, then goes back to 3500, engine nearly at full temp.

is this pressure low or ok? when i rev it the pressure increases to 100,000PSI++++

also when i plugged OBD back into car there was another code but its gone now, the code was U1401

Chrysler: Implausible Engine Speed Signal Received
Dodge: Implausible Engine Speed Signal Received
Jeep: Implausible Engine Speed Signal Receive

this ^^ is all i could find on the code

does this look like Crankshaft position sensor?

ambient air temp is reading -7.6F, would this have anything to do with it? I think there is a problem with that sensor, but i dont think it should cause a problem


edit: this is a very small chunk of my data log

01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E5 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E4 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]



An invalid data length was received.
01 44: [NO DATA]
01 00: [7E8 06 41 00 98 3B A0 13 00
7E9 06 41 00 98 18 00 01 FF ]
No Data Received: CommandEquivalenceRatio, Invalid Count: 1
01 05: [7E8 03 41 05 80 00 00 00 00
7E9 03 41 05 7D FF FF FF FF ]
01 00: [7E8 06 41 00 98 3B A0 13 00
7E9 06 41 00 98 18 00 01 FF ]
01 0D: [7E8 03 41 0D 00 00 00 00 00
7E9 03 41 0D 00 FF FF FF FF ]
01 10: [7E8 03 41 10 E2 00 00 00 00 ]
An invalid data length was received.
01 0D: [7E8 03 41 0D 00 00 00 00 00

dont know if this means anything to anyone but just encase.

Thanks

 

[QUOTE=Plutoe;5788983]I see, i'll give him a ring tomorrow and see if I can drive the car out to him without killing myself ha. Hopefully he finds the problem.

Thanks for the help, i'll report back when I have a solution.

Charlie

 

Hi,

I had crank position sensor CKS ordered so I took it, its a cheap part so I though if it doesnt work its worth ruling it out.

Anyway fitted the part, could'nt get the f**king shield back on, its a nightmare to fir with the tight space, anyway I've took the car for a test drive and no problems so far so fingers corssed

 

problem resolved, Crankshaft position sensor was at fault although not showing classic symptoms of shutting off and not starting up, it shut off and started up straight away.