You can change a lot of things that provide current, but if you take the time to read the earlier posts again you'll see that you may not even have an EHA current problem. If chuck read the year model right on his CD, 90% deals with EHA current. My Mercedes Benz factory code book published in 93 says 90% isn't used til 90 year model. You could also just have a dead O2 sensor that is reading lean. You could unplug the O2 sensor, go into open loop, and check the output of the sensor with a 10 meg voltmeter. If you read about .2 or .3 volts steady signal, that would send a lean signal causing the mixture to go steady rich at about 90%. We need to find out who has the misprint in their reference material and go from there
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