92 accord idle surge

I have a 5-speed 92 accord lx, recently converted to R-134 a/c. Now
when I run the a/c, I get an idle surge from 500 up to around 2,000
then drop back to 500, back up again. May stop after a few surges, or
keeps going until I turn the a/c off. I have read about several
possibilities, I just want to have a clear idea before I take it to a
shop. I have read about the Electrical Load Detector, and an a/c idle
boost solenoid valve. The car is fuel-injected. Also read about the
possibility of just updating the computer. I work as a mechanic in a
factory, but little experience on cars. Can I troubleshoot this kinda
easily, or does it sound like a particular problem that needs a shop
fix? Thanks alot, d4

 

It's either that or the Fast Idle Valve.

You have a large air leak into the intake. That unplanned air usually comes
from the auxiliary air inputs.

 

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Tegger's probably right, but be sure your coolant reservoir is full
above the MIN mark, even up to MAX. Any air in the system will throw out
the computer's inputs and idle will suffer. Check it again for two days
in a row to see if it drops as engine sucks it in.

'Curly'

 

Something I forgot to mention: When the engine is hot and the idle is
surging, remove the air intake tube from the throttle body. Cover the LOWER
port in the throttle body with your finger. If there is suction at that
port, the Fast Idle Valve is stuck open. If there's no suction, then it's
fine and your air leak is probably the A/C idle boost valve.