Matatk wrote:
I'm not sure exactly what you're looking at in the manual. The ZR1 has 16 fuel injectors, though.

Rough idle can be caused but multiple issues, one not mentioned is a dirty or malfunctioning IAC. The throttle body may also be carboned up. Two things to look at that are maintenance items.

Also, a bad O2 will distort your fuel trim levels. Another maintenance item. I've read non heated O2s should be replaced every 30,000 miles.

Matthew