Engine Revs Up After Blipping Throttle

[AccordWarrior]

Hi all,

For the past week or two, I've had my cruise control unhooked, and the vacuum line that runs to it left open. Bad idea, I know, but I didn't have time to get the plugs. Tonight, I bought caps for the line. I capped the one for the cruise control.

I also capped a few of the lines on my intake manifold. When I installed my AEM intake, it was different than my generic SRI. There was no nipple for the vacuum line from the intake manifold. I remember reading in the instructions found online that they provide you with foam for hole. At the time I just left it open to the air (bad I know). However, tonight I capped that hose. I had also capped the second from the back hose as well, which was the one that ran to the original black box near the battery.

After I capped both lines, I reset the ECU, hoping this would help my car run a little smoother. When I restarted it, I was just letting it idle and I bumped the throttle at the TB. It was then when I noticed that even a light touch would cause the RPM's to jump a lot.

Basically what I'm wondering is if you can't cap that line that was supposed to run to the intake tube?

I recorded a video of what the car is doing.



If you notice it makes a popping sound when it's bumped. I also revved it a bunch of times to see what was happening and it was just running like ass.

I'm going to uncap that line tomorrow and reset the ECU again...but I guess I'm just wondering how to properly filter that line without it.

[NAiL05]

So you have a hole in the intake itself or the manifold. A hole around the intake wont effect anything (my ghetto piping rubbed a hole via abs module and didnt find out till a week later). If its around the manifold I would look for that. Try driving around with the car for a while see what happens. Anyway when you say it revs up you mean you give it a lil but throttle goes up more than you expect? Have you checked sticking throttle cable or throttle body at that?

[almostJDM]

i think hes talkin bout the vacuum line that runs fron the TB to the intake piping

[AccordWarrior]

i think hes talkin bout the vacuum line that runs fron the TB to the intake piping

Yeah, that one. I guess you can't cap it or something. I'll have to remove the cap and reset my ECU.

I was just wondering what I should do with it.

[owequitit]

That tube actually runs to the air boost valve which is completely un-necessary.

It simply helps the car start.

It most likely will rev slightly higher due to less intake restriction, but not a lot.

My guess would be that the clicking is your IACV popping shut.

I have just been dealing with this on a kids H22 swap here in town.

It would rev really high and hang onto revs when you let off the gas, and they you would hear it click and the idle would come down.

We cleaned it, with good carb cleaner which helped the symptoms a lot, but didn't completely alleviate it. Probably more intense cleaning would clear it up, as they tend to get carbon coked.

Maybe you sucked something in, but I doubt it, so my guess would be a cleaning.

[almostJDM]

yea i iacv would do the same thing when i had my odb2 f20b intake/tb on i woudl start it up and it would rev to about 3k then id hear the iacv click loudly then the revs woudl drop to aroudn 1300 and bounce but now it doesnt do that anymore now that i have the h22 plenum and tb on

[AccordWarrior]

Eh, I uncapped that line, and it's running back to normal.

The popping definitely wasn't my IACV though. I had cleaned it about a year ago, but ever since then it's been running weird. I'll have to take it back off and re-clean it.

[almostJDM]

glad to hear you fixed it

[owequitit]

Eh, I uncapped that line, and it's running back to normal.

The popping definitely wasn't my IACV though. I had cleaned it about a year ago, but ever since then it's been running weird. I'll have to take it back off and re-clean it.

Perhaps your air boost valve has failed, and it opening when it shouldn't be.

[SN2BH22CB7]

Hmmm....what grade of fuel are you using???

I just slapped PREMIUM in my Accord...and for some reason..its running smoother than creamy peanut butter on a hot day!

the funny idle...I had that...but when I upgraded to PREMIUM from the usual 87 octane....the funny idle almost like yours is gone!...I think my idle had something to do with the crappy 87 octane fuel!