View Full Version : 87 Honda Prelude What is the name of this emissions part?

05-07-2020, 07:02 PM

This is my first post so here we go!

I have a 1987 Honda Prelude 1.8L dual carb and I am looking for the name of the part that is vacuum line hooks up to. I believe it is a nippodenso part, but it has no label. Also, I was stopped at a stop sign and my idle dropped and the car stalled. It would not start again until I covered the vacuum line and then it idled fine. Could this part be causing an idle issue? I have a picture of the part and highlighted it (it is taped up). I also took a picture of the vacuum diagram and highlight the part I think it is as well.

05-07-2020, 07:18 PM
After looking at another thread, I believe the vacuum line that hooks up to this part also hooks up to the igniter module if that helps identify the part more easily.

05-07-2020, 07:25 PM
After looking at my picture more thoroughly, I think that part is labeled as air control valve B. Would that be correct and causing my issue?

05-08-2020, 03:03 PM
The part you circled in the engine bay is the anti afterburn valve. Unfortunately if its not working you wont be able to get a new one. The car will run without it but since I see you live in the worst state possible to have this car I don't know if it will pass emissions. lol.

05-08-2020, 06:40 PM
Thank you for ID'ing it! Yes, California is terrible for owning cars 75 and after especially if they are older ones with issues passing smog. I think the part is working but a piece of it broke that fits into the hose. My dad used JB weld to hopefully hold it in place.