ok i have a d16z16 swap in my 91 crx dx and when I start the car it idols up 2 about 1500 then it drops down 2 about 800 rpms then when sometimes it will jump up to about 1200 rpms then drop down to about 500 rpms does anyone know what could be causing this

 

it sounds like a vacuum leak...one way to help that is by spraying carb cleaner in the TB while the car is ON, that will stop small leaks. If that doesnt fix the problem u have a larger vacuum leak somewhere or a faulty MAP...

 

O ok thanks man I will go try that