The car idles rough when the car is started cold in the morning. Cold in Hawaii is 65F. There is also a clicking noise where the idle speed control / cruise control module located in the false floorboard of the front passenger. The non-electronic throttle body (Non-ASR ETA) also clicks simultaneously with the ISC/CC module. The RPM hunts between 500-1000 RPM only for 3 minutes then stabilizes to 600 RPM.
When the engine warms up to 60C via the temp gauge, the clicking stops and the engine runs and restarts fine all day. Then it's the same clicking next morning. I also have a check engine code 17 indicating a data exchange error between modules.
Cruise control works. The biodegradable wiring harness has been changed. The over voltage protection relay was tested and works fine. All fuses were replaced. Engine coolant and air intake temperature sensors were replaced.
I've asked in MB forums and they suspect either the original throttle body with the biodegradable wiring insulation or the ISC/CC module. I don't think it's either though because the symptoms does not tally with a typical non-ASR ETA failure which includes loss of cruise control and erratic engine idle at all temperature. I also checked the ISC/CC module's CAN resistance value and it is fine. I think it's an electrical issue that's temperature dependent.
Any inputs from anyone with experience on these cars?
When the engine warms up to 60C via the temp gauge, the clicking stops and the engine runs and restarts fine all day. Then it's the same clicking next morning. I also have a check engine code 17 indicating a data exchange error between modules.
Cruise control works. The biodegradable wiring harness has been changed. The over voltage protection relay was tested and works fine. All fuses were replaced. Engine coolant and air intake temperature sensors were replaced.
I've asked in MB forums and they suspect either the original throttle body with the biodegradable wiring insulation or the ISC/CC module. I don't think it's either though because the symptoms does not tally with a typical non-ASR ETA failure which includes loss of cruise control and erratic engine idle at all temperature. I also checked the ISC/CC module's CAN resistance value and it is fine. I think it's an electrical issue that's temperature dependent.
Any inputs from anyone with experience on these cars?
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