Hi folks, I just bought a 93 coupe last month and it's my first 'vette. The engine is normally idling at 500rpm according to the tach on the dash, but that seems a bit low to me. Occasionally when I crank it up it struggles to idle at first, especially if the AC compressor is running, and it has even cut off a time or two right after cranking. Once it gets going, it idles just fine at 500rpm's though. This car has 62k miles on it and the engine appears to have had some work done to it. There's a sticker on the radiator cowl that states it is equipped with Comp Cam Magnum lifter arms, and the motor has a MSD Ignition system on it. I'm not even sure if it has the original Optispark box under the water pump?? Someone added some Comp Cam and Summit Racing decals that are stuck to the bottom of the hood. The motor does seem to have a mild cam in it, but I have no way of knowing for certain. This car also has a Magnaflow exhaust system, so someone has spent some money on it in the past. What should my LT1 small block 5.7L idle at? If I wanted to increase it to, to let's say.... 700 rpm's, how do I go about it? Is that set in the ECM meaning you have to flash it to change it? Or should I just leave it be?

 

You should be able to adjust the the torx screw on the side of the throttle body that the accelerator cable attaches to. turn it clockwise to incress idle speed. The ECM controls the idle speed with the IAC, if it's working correctly you shouldn't have an issue. The TPS is also involved. Try the screw adjustment.