Rep Power: 0

I have an after market cat back exhaust and headers on my 2000 Honda civic ex. The car runs fine and doesn't have any issues besides the idle. It seems that the car will idle fine then when I stop it will sort of sputter and then catch back up to a normal idle. Any idea what is causing this?
Note:I don't have a cat after I put the aftermarket exhaust on. Just a straight pipe. Aldo I had to modify the o2 sensors in the straight pipe because it kept throwing a code. I used a spark plug non-fowler to pull it out of the exhaust stream a bit. No more check engine light.

 
Rep Power: 173

How long have you had the new exhaust? When did the problem start?

 
Rep Power: 243

Could be a dirty IACV or throttle body. Carbon gets built up and causes idle issues.

 
Rep Power: 0

“2000 civic ex (d16y8) idle problems”

I have this exact problem right now, in 2022, minus the new muffler.

[ QUICK ANSWER: Maybe just blow throttle body cleaner through the intake/throttle body? ]

Could be a dirty IACV, throttle body (as mentioned earlier), or a loose vacuum hose when I reset all the hoses.

Don’t want to tear up the gaskets on the IACV or throttle body, they look good and I don’t need more work.

See pics attached.



^^ Air filter assembly removed from throttle body.

2000 Honda Civic EX Coupe
D16Y8
Rough idle


^^ Inside the throttle body.

2000 Honda Civic EX Coupe
D16Y8
Rough idle


^^ Near PS firewall.

2000 Honda Civic EX Coupe
D16Y8
Rough idle


^^ Top view of idle control assembly.

2000 Honda Civic EX Coupe
D16Y8
Rough idle