This one has me stumped. I have a partial throttle miss that clears up under heavier acceleration. I replaced plugs and wires (75K-the plugs were fine but the wires made a difference) and last weekend cleaned the ICS port and throttle plate but it didn't make any difference. I also read the TPS with an ohm meter and it doesn't have any drop out spots. No vacuum leakes that I can find. I notice that this miss does not occour when the engine is cold but after it enters closed loop. I've sprayed water on the wires trying to get a problem to show up but no go. Usually this sort of thing is ignition related but I'm running out of place to look. Anybody seen this before?

 

It just occoured to me that this happened after installing a new EGR valve. Do you suppose it could be defective right out of the box? It isn't enough to set a code in any case.

 

I dont think EGR would make the car miss. It would cause it to run a "rough" at an idle and such.

I had a problem at 1400 rpm where the car would miss like crazy. Optispark, plugs, wires and coil later, the problem was gone.