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Old 09-18-2002, 04:14 PM
stevebfl stevebfl is offline
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Join Date: Mar 2000
Location: Gainesville FL
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I hate to break this up, but component testing is a poor way to do diagnostics. Diagnostics should be through performance testing, not the testing of design criteria. Somewhere a bjillion words back was a condition existing on a car.

If you wish to evaluate the potentiometer, measuring airflow rate, then the proper way is through results. Two forms: raw data which is not resistance but voltage. The control unit is looking for voltage. But it is more interested in rate of change of voltage. This spec isn't available but the result is. The result is an appropriate snap increase in EHA current. My best guess is 5-10ma from nominal.

If you wish to fix a car you need a hypothetic system answer to explain basic testing: What is the base complaint? Does an EHA current problem explain the condition? Is it a general lack of fuel? Is it fuel? All fuel control starts with the hydraulics. It is only modified by the control electronics. The final answer is to see the EHA current as expressed by differential pressure. Lots of test values.
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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician
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