so i bought this 99 civic with d16z6 from my friend and fixed alot of stuff i got it running and it has a rough idle to it and smoking from the exhaust. it could be the timing is off but figured id ask you guys for help. i did a code check and nothing came up. when i push the gas it revs slow but the sound from the exhaust quits and it seems like its sucking air back in. vacuum issue maybe? btw it does idle at 2500-3000 rpm any help would be great thanks!

 

Check the iacv
Check the wiring to the iacv.
Put a timing light on the motor.
What ecu?
Set the base idle.

 

i'll check that and clean it up tomorrow. i need to buy a timing gun also so i can set that right and make sure the timing can be out if it still acts that way. if these dont work i'll be back for more help. thanks!!