Hello,

I have a 1966 Accord. 4cylinder, 5 spd. Recently - within the last month or so - the engine has been revving from idle to about 1500 rpm or so and then back again. During the same timeframe, I've noticed my electric cooling fan has been running more and more after I shut the engine off.

I have the car at my mechnic now up on the rack and he says I need a new radiator. Says that the system is losing fluid and that the low coolant level is throwing off sensors that control the idle.

Does this sound right?? Any advise appreciated!!!!

Thanks, Joe

 

Yes, air pockets in the cooling system is a common cause for surging idle. Usually it's just a matter of bleeding out the air (there's a bleed screw at the thermostat housing). But if your radiator IS leaking, that will continue to put more air into the system after you bleed it out.

Search around here. I've posted a few times about setting the "BASE idle". Find that procedure & do it after your radiator is replaced.

 

CAUTION:

• All SRS wire harnesses are covered with yellow insulation. Before you disconnect any part of an SRS wire harness, disconnect the airbag connectors.
• Whenever the ignition switch ON, or has been turned OFF for less than three minutes, be careful not to bump the SRS unit; the airbags could accidentally deploy and cause damage or injuries.

1. Start the engine. Hold the engine at 3,000 rpm with no load (A/T in [N] or [P] position, M/T in neutral) until the radiator fan comes on, then let it idle.
   
   
   
   
   1. Pull out the service check connector located behind the glove box. Connect the special tool.
   2. Check the idle speed.
      
      
      
      
      
      
      1. Connect a timing light to the No. 1 ignition wire.
      •  
        • Point the light toward the pointer on the timing belt cover.
      1. Adjust ignition timing, if necessary, to the following specifications: Ignition Timing: 15°±2°BTDC (RED) at 700 +/- 50 rpm with shift lever in neutral position (A/T: [N] or [P] position) and electrical systems turned off.
         
         
         
      2. If the ignition timing is incorrect, replace the ECM/ PCM (there is no way to adjust ignition timing).
      3. Tighten the adjusting bolts.
      4. Disconnect the special tool from the service check connector.

I Hope This helps a little