BenzWorld Junior Member
Date registered: Nov 2009
Mentioned: 0 Post(s)
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Help! ML320 looses acceleration at all speeds
My 1988 ML320 looses power at all speeds (175k miles). While driving straight at highway speeds, the engine rpm drops all of a sudden slowing down the vehicle from 65 mph to 40mph within several seconds. Pressing the accelerator paddle does not have any effect. However most of the time power comes back. Car speeds up, but again looses power. When engine power and RPM comes backs, it thumps and jerks the car. Sometimes, a little tap on the brake helps restore power. This issue gets worse with each passing day. It happens more often and now happens at lower speed. I have no codes. I checked with Carsoft. Nothing. I suspected ABS and traction control. I disconnected a speed sensor to disable ABS ETS. Same problem persisted. I do not have ESP. I checked brake rotors. They were not hot after driving. I replaced fuel filter. I cleaned intake with seafoam through vacuum line. Changed engine oil (0W40), changed transmission fluid and filter (shell ATF134). Erased adaptive learning using carsoft. No improvement. The previous owner replaced mass airflow sensor. My next guesses will be CPS, fuel pump, throttle position/paddle transducer or throttle actuator. Any guesses? I will borrow a fuel pressure gauge and check the car out. Any suggestions? Please help.