Cold start fast idle delete

[jiggernaut]

Hi,

I was wondering if anyone has gained any improvement by blocking off the cold fast idle valve, a separate valve from the IAC on 94' Accords? Currently my engine idles around 1500 rpms on cold starts and slowly works down to 800rpms as it warms. I'm thinking about plugging off to lower rpms on cold starts. One foreseeable scenario, is that the engine wouldn't reach open loop as fast and may negate the lower idle rpm fuel savings?

Also, my 94' is an OBD1 car, thus only one O2 sensor. So, would hollowing the cat bring gains in mileage?

Thanks in advance, Jig

[Daox]

Hollowing out the cat is not only illegal, but completely unnecessary. Unless it is plugged, its not hurting mileage at all. That, plus I like clean air.

I'd leave the fast idle alone too. Not only does it heat the car up faster for defrosting and heat, it also gets the engine warm so oil flows properly, the transmission warms up and reduces drag and also so you can get into open loop and stop dumping a super rich mixture into the engine just to keep it running.

[Mustang Dave]

What's cold idle? Start it and drive; idling wastes fuel.

[Tango Charlie]

Yup, what Dave said.
Use a block heater or an oil pan pad heater to get the engine up to operating temps faster. Even a trouble light with an incandescent light bulb slid under the engine will give it some preheat.
And don't idle!