Strange Idle Problem
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1992 300CE
Strange Idle Problem
1992 Mercedes 300ce M104.980 3.0 24V CIS
I recently had a problem where the car wouldn’t start. I have replaced the crank positioning sensor, the coil and the EZL. The car would now start but it had a big stumble under hard acceleration and what felt like a miss under constant throttle and a high idle. I replaced the EZL again with another rebuilt unit from the same place and the stumble and miss are cured. The idle can be normal or can be 1200rpm or over 1500rpm. It doesn’t really hunt, but varies each time you start the car. It seems to maintain the same idle speed as you drive. If you turn the car off and then on again you get a different idle speed usually lower than the previous. If you wait 10 or 15 minute it might be high again or not. Could this be the EZL again? The company that rebuilds them maintains that none of my problems were the EZL, but swapping the second EZL cured most of my issues. I have checked for vacuum leaks and found none and it isn’t throwing a related fault code. The car ran and idled great before the no start issues and nothing other than the parts I have mentioned has been touched. Any thought or advice would be appreciated. Thanks
I recently had a problem where the car wouldn’t start. I have replaced the crank positioning sensor, the coil and the EZL. The car would now start but it had a big stumble under hard acceleration and what felt like a miss under constant throttle and a high idle. I replaced the EZL again with another rebuilt unit from the same place and the stumble and miss are cured. The idle can be normal or can be 1200rpm or over 1500rpm. It doesn’t really hunt, but varies each time you start the car. It seems to maintain the same idle speed as you drive. If you turn the car off and then on again you get a different idle speed usually lower than the previous. If you wait 10 or 15 minute it might be high again or not. Could this be the EZL again? The company that rebuilds them maintains that none of my problems were the EZL, but swapping the second EZL cured most of my issues. I have checked for vacuum leaks and found none and it isn’t throwing a related fault code. The car ran and idled great before the no start issues and nothing other than the parts I have mentioned has been touched. Any thought or advice would be appreciated. Thanks
