The extra load of my '94's Accord's AC often causes such a drop in idle
speed that the engine dies when trying to start up after a traffic light
change, especially on a slight uphill. This forces me to turn off AC
when stopping at traffic lights and turn it on again after moving.
Without AC the idling RPM is about 750, which is about normal.
Isn't the car's computer supposed to compensate for the AC load?
Yes. That's the A/C Idle-Up signal.
From what I see in the various shop manuals, failure to idle-up is usually
due to a corroded or internally-broken wire between the compressor, the
compressor clutch relay, and the ECU.
The ECU sees the A/C signal from the wiring, then boosts idle to
compensate. If that signal never comes in, the ECU will not know to
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