reference resistor, do you mean the "TA", throttle actuator that has the potentiometer?

mnstang, I assume you mean the EA Module itself??

My opinion is that it's the EA module itself. It has all the symptoms of having a heat problem. There's no other codes set, and the 'clincher' is ASR code 30 that says it can't talk to the EA module. And that makes this problem occur. Am I correct?

Never had this problem and basically in the dark. Your knowledge and experience is appreciated. If it is the harness, would it only do it when 'hot' as opposed to all-the-time?

Next week, I'm going to swap it with another EA unit and see what happens.

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Regards . . . . JimF
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'94 S500 Cpe

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