kiko11

This is a great forum. I have a '93 S10 Blazer 4.3L with a VIN "W" code 4L60-E 4X4. I could use some help with Code 35. The Check Engine light goes on only after a short time sitting at a stop light or in traffic. The light goes out after moving down the road a short distance. I have replaced the IAC, cleaned the area for the pintil, replaced the PCM, cleaned the LEGR, replaced the ignition wires, gapped the new plugs to .045", replaced the rotor button and cap. Temporaly plugged the small vacuum line the vacuum line to the brake booster. No change. I would be most grateful for a solution. The vehicle only has 112K miles. Hardly broke in. The body is perfect inside and out. The high idle problem is approximately 750 to 800 rpm with and without the A/C engaged. The high idle is suspect. However, not sure if this is really setting the Code 35. The A/C clutch cycles from the I/P. Aside from this the whole truck runs very well. I have missed something.. I can sure use some help. Thank you Dave

old_master

DTC 35 description is: IAC valve or circuit: idle speed control circuit shorted. Two things can cause that DTC, one is a shorted IAC, which you have already replaced, the other is one, or more, of the circuits for the IAC is shorted. Trace each circuit from the ECM to the IAC for a short to ground or to another IAC circuit. The SES light not being on constantly indicates there may be an intermittent short circuit. You might have to gently wiggle the harness to duplicate the short condition.