A200 engine shut off while driving
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A200
A200 engine shut off while driving
Hello all! My 2018 w177 A200 encountered an unusual engine issue last month.
The car has been parked at the garage for roughly a week, engine start all as normal. Drive off and in about 5-8 minutes, the engine cut off and all the warning light displayed on the dashboard. Stopped in the middle of the traffic, tried to restart the engine but without success (quite similar to low battery voltage symptoms). Then I managed to push the car to the side and called for a tow.
Soon the dealership has diagnosed fault code and cylinder 3 misfires. But they just couldn’t find any clues of what’s causing the problem.
After a month of wait, finally tracked down to the front SAM module. The dealer informed me that it was SAM control unit internal fault that caused the engine shut down and misfire. I got the car back and it drive fine for a week now. And really hope this won’t happen again, it’s really terrifying when the engine quit while driving. Luckily it wasn’t happened on the highway.
the following are the check from the dealership.
“Check vehicle shut down while driving - all the lights flashing on the screen
Sam control unit internal fault
Inspected, confirmed the concern, vehicle misfire then cut off during inspection, fault code current misfire on
cylinder 3,4 and fuel pressure too low, checked fuel pressure through xentry, result shown 6.8bars ok, c/o swap spark plugs between 3,4 to 1,2, coil pack between 3,4 to 4,3, checked fault counter shown misfire on cylinder 3, swapped coil pack 3 to 1, still shown misfire on cylinder 3, require more time to take fuel sample, swap fuel injector, compression test, leakage test (2-3hours)
c/o take fuel sample seem ok/clean, c/o swap fuel injector between 2 and 3, recheck fault counter still shown up to 200-300 at cylinder 3, but after test drive back to 3-6 and
can not reproduce when engine hot, c/o compression test and leakage test, result shown ok in spec, discussed with foreman, require more time for software update, drain old
fuel in the tank, then require 20L fresh petrol 98 and cold
start inspection, let customer aware if still shown misfire
on cylinder 3 after new fuel and software update, might need
to remove cylinder head cover on intake and exhaust side for
further inspection
c/o drain fuel out, put 20L fresh petrol in, still shown
misfire on cylinder 3, but only can feel vehicle idling
rough intermittently, driving fine no misfire, c/o another
compression test and leakage test when engine cold, result
shown in spec ok, during inspection notice voltage low
through xentry, kept around 12v, also the whole screen
flicking intermittently, require more time for further
inspection and require more info from customer. Suspect
front sam control unit is the cause of the voltage issues
Swapped sams from a donor vehicle and monitored - vehicle didn't fault Removed Carried out initial start up
All ok”
I hope the info helps, if anyone got a similar issue?
The car has been parked at the garage for roughly a week, engine start all as normal. Drive off and in about 5-8 minutes, the engine cut off and all the warning light displayed on the dashboard. Stopped in the middle of the traffic, tried to restart the engine but without success (quite similar to low battery voltage symptoms). Then I managed to push the car to the side and called for a tow.
Soon the dealership has diagnosed fault code and cylinder 3 misfires. But they just couldn’t find any clues of what’s causing the problem.
After a month of wait, finally tracked down to the front SAM module. The dealer informed me that it was SAM control unit internal fault that caused the engine shut down and misfire. I got the car back and it drive fine for a week now. And really hope this won’t happen again, it’s really terrifying when the engine quit while driving. Luckily it wasn’t happened on the highway.
the following are the check from the dealership.
“Check vehicle shut down while driving - all the lights flashing on the screen
Sam control unit internal fault
Inspected, confirmed the concern, vehicle misfire then cut off during inspection, fault code current misfire on
cylinder 3,4 and fuel pressure too low, checked fuel pressure through xentry, result shown 6.8bars ok, c/o swap spark plugs between 3,4 to 1,2, coil pack between 3,4 to 4,3, checked fault counter shown misfire on cylinder 3, swapped coil pack 3 to 1, still shown misfire on cylinder 3, require more time to take fuel sample, swap fuel injector, compression test, leakage test (2-3hours)
c/o take fuel sample seem ok/clean, c/o swap fuel injector between 2 and 3, recheck fault counter still shown up to 200-300 at cylinder 3, but after test drive back to 3-6 and
can not reproduce when engine hot, c/o compression test and leakage test, result shown ok in spec, discussed with foreman, require more time for software update, drain old
fuel in the tank, then require 20L fresh petrol 98 and cold
start inspection, let customer aware if still shown misfire
on cylinder 3 after new fuel and software update, might need
to remove cylinder head cover on intake and exhaust side for
further inspection
c/o drain fuel out, put 20L fresh petrol in, still shown
misfire on cylinder 3, but only can feel vehicle idling
rough intermittently, driving fine no misfire, c/o another
compression test and leakage test when engine cold, result
shown in spec ok, during inspection notice voltage low
through xentry, kept around 12v, also the whole screen
flicking intermittently, require more time for further
inspection and require more info from customer. Suspect
front sam control unit is the cause of the voltage issues
Swapped sams from a donor vehicle and monitored - vehicle didn't fault Removed Carried out initial start up
All ok”
I hope the info helps, if anyone got a similar issue?
