QuestionI have a 2002 S500 w/ 160K miles. Car started to give a false neutral when traveling about 5 MPH. Trans would spin briefly then pop in. Switched to Wet mode and issue reduced 80%. Still happens when it is raining heavily. Check engine light shows air mass meter but replaced and still get same error. Transmission cleaned out and looks good. No issues at higher speed. Seems like a computer signal to trans issue. Car will stall and cut off at times. Then, upon restart, no issues as if computer reset. Happens 20% of the time with primary symptom is feeling of nuetral - push accelerator but car just thinks for about 5 seconds then proceeds. Mechanis suspect a wiring issue especially when error happens most during wet weather. But overall feels like a signal/software issue. Any thoughts, experience or advice?
AnswerPaul,
Welcome to the world of bytes and bits. The transmission shifting is integrated into the computer system that relies on throttle position to determine shift speed among a myriad of other things.
The Battery and charging system should be in tip top shape. If the battery is more that two years old, I would install a new unit.
I tend to think that you have a grounding problem. These issues are particularly difficult to locate because they do not happen on a continuous basis.
I would reset the computer. Try this. Stay with me now.... turn off all accessories, and the radio. Release the hood latch. Exit the vehicle and lock the drive door with the key, wait until all the locks set before removing the key.
Open the hood. Take of the (-) then (+) battery terminals. Clean the terminal ends with a battery brush and the battery post. After 30 minutes re-install the terminals (+) then (-). Tighten securely. Close the hood and with the key unlock the doors.
This is like cold booting a computer at home.
It should set all the parameter back to original configuration.
Start the car and take a test drive. See it the problem is gone or improves.
Let me know what you find out.
Good Luck
Robert
